1. Field
The field of the invention is that of the Internet ofThings. More specifically, the invention
relates to a gateway architecture which permits the deployment of wireless sensor networks,
5 specifically on a large scale, and to the interconnection of such networks with other networks such
as, for example, the Internet.
2. Prior art
The Internet of Things is developing rapidly. This development is accompanied by the
emergence of new applications, which extend beyond the traditional scope of homes or businesses
10 and are integrated in far larger infrastructures. Specifically, the concept of "smart cities" falls within
the context of this development. By the large-scale deployment of wireless sensor networks, or
other communicating objects, it becomes possible to offer new services to individuals, or to the
authorities responsible for municipal administration. The range of possibilities is extensive. In this
way, street lighting can be optimized, for example by the adaptation thereof to road traffic
15 conditions at any given time. Parking management can also be facilitated, by the real-time
notification of drivers of available parking spaces using sensors which are integrated in each parking
space. This contributes, for example, to the reduction of vehicle fuel consumption, and
consequently to the reduction of pollution.
The deployment of these wireless sensor networks represents a particularly attractive
20 development opportunity for mobile telephone operators. In practice, the latter are ideally
positioned: firstly, they have developed expertise in the field of the deployment of large-scale
wireless networks, and secondly they already have a proportion of the requisite infrastructures for
the deployment of such a network in place. For example, installation sites (masts, posts, high points,
etc.) for the relay antennae used in mobile telephony can also be employed for the accommodation
25 of antennae and base stations which are deployed for the operation of a wireless sensor network.
The function of these base stations is the reception and transmission of data from and to wireless
sensors which are present within their zone of coverage (radio access), but also the relaying of these
data to facilities for the processing thereof, for example servers which are accessible on an IP-based
network (IP: "Internet Protocol"). Base stations also fulfill an interfacing role between the wireless
30 sensor network and other networks, for example a wide-area network such as the Internet, and,
accordingly, are also described as "gateways".
A number of radio access technologies are available for the deployment of wireless sensor
3
networks. By way of illustration only, and not by way of limitation, mention may be made of LoRa'M,
Sigfox'M or WM-bus ("Wireless Meter Bus") technologies, which are specifically based upon
different types of modulation. These technologies can operate in different radio frequency bands
(for example in private frequency bands, subject to the acquisition of a license; or in unrestricted
5 frequency bands, such as ISM bands), using a wide variety of types of antennae (sectorized,
polarized, omnidirectional, etc.). Accordingly, there are a multitude of potential configurations, and
the determination of the technical solution to be preferred generally results from the appraisal of
numerous criteria. Thus, the topography of the zone of deployment, the density of sensors to be
addressed, and the targeted quality of service, together with regulations in force in the territory
I 0 considered (unrestricted frequency bands differ, for example, between the USA and France) are all
factors, among many others, to be considered in the deployment of a wireless sensor network.
Existing gateways for the deployment of wireless sensor networks have limited scalability:
in general, they are designed for the management of a single type of radio access technology, in a
single radio frequency band. These gateways generally provide only limited connectivity, in terms
15 of potential configurations of antennae, or may even dictate the use of the antenna supplied.
Finally, in the majority of cases, they can manage only a single type of interface (hard-wired, or
WiFi, or 3G/4G, for exam pie) with another network (such as the Internet, for example). While these
gateways are particularly appropriate for the deployment of wireless sensor networks on a small
or medium scale- in contexts of application which are relatively fixed and closely-managed- they
20 are no longer suitable for the deployment of wireless sensor networks over very extensive and
constantly changing zones- for example on the scale of an entire city- where a high degree of
responsiveness and adaptability are required. These existing gateways, which must be entirely
replaced in response to the slightest requirement for a network upgrade, are therefore unable to
accommodate the various issues associated with the scheduled expansion of dedicated networks
25 for the Internet of Things: a constant and substantial increase in the number of sensors to be
managed within a single territory, the diversity of radio access technologies to be accommodated,
the diversity of frequency bands used, the diversity of types of antennae to be managed, etc.
There is thus a requirement for a new type of gateway for wireless sensor networks or other
communicating objects which provides sufficient adaptability to permit the suppliers of solutions
30 for the large-scale Internet of Things to upgrade a network already deployed in a simple and rapid
manner, at a moderate cost; there is also a need for the straightforward transposition of a solution
from one territory to another, notwithstanding the differences (topographic, regulatory, etc.) which
4
may exist between these territories, in order to provide an easier response to the dictates and
expectations of these new territories.
3. Summary
The proposed technique offers a solution which eliminates at least some of these problems
5 from the prior art, by means of a modular gateway architecture for a wireless sensor network.
According to a first aspect, the proposed technique relates to a digital radio modem for the
modulation and demodulation of a digital signal, in accordance with a preselected radio access
technology, wherein said digital radio modem is characterized in that it comprises a protective
frame and a plurality of communication interfaces which are arranged within said frame.
10 Thus, the digital radio modem according to the proposed technique is not integrated, for
example, in a printed circuit: it has its own dedicated frame, within which different communication
interfaces are arranged. In this manner, the digital radio modem provides a degree of flexibility in
use: it constitutes an independent physical unit, which can easily be assembled or disassembled in
conjunction with the deployment of a gateway for a wireless sensor network.
15 In a particular form of embodiment of the proposed technique, said plurality of
communication interfaces comprises at least a first communication interface with a complementary
device, and at least a second communication interface with an analog radio interface module.
The digital radio modem thus has at least two communication interfaces.
The first communication interface permits the connection thereof to a complementary
20 device, which may be a device of the same type (namely, another digital radio modem according to
the proposed technique) or a device of another type (for example a control device, an electric
power supply device, or a device for the management of the connection with another
communication network). In the first case, the digital radio modems are mutually connected by the
cooperation of the respective first communication interfaces of said devices. In the second case,
25 the complementary device to which the digital radio modem according to the proposed technique
is connected itself comprises at least one communication interface which permits the cooperation
thereof with said at least one first communication interface on the digital radio modem. This first
communication interface assumes, for example, the form of an SPI ("Serial Peripheral Interface")
connector. In this manner, devices thus connected share at least one common data bus.
30 The second communication interface permits the connection of the digital radio modem to
an analog radio interface module. In this manner, by the combination of these two independent
physical blocks, it is possible to constitute a radio interface device which, by the addition of an
5
10
5
antenna, permits the reception and transmission of data from or to at least one remote sensor. This
second communication interface can also assume the form of an SPI ("Serial Peripheral Interface"»)
connector, thus permitting the constitution of a data bus between these two elements, once they
are mutually connected.
In another particular form of embodiment of the proposed technique, the digital radio
modem comprises at least two first communication interfaces with a complementary device,
wherein these communication interfaces constitute the terminations of at least one data bus
employed by said digital radio modem for the transmission and/or reception of data to and/or from
at least one complementary device.
In this manner, due to the presence of these at least two first communication interfaces, it
is possible to interconnect a number of digital radio modems according to the proposed technology,
but also to interconnect the latter with compatible complementary devices of other types, such
that all the devices thus connected share at least one common data bus.
In a further particular form of embodiment of the proposed technique, the digital radio
15 modem is characterized in that said preselected radio access technology is included in the group
comprising the following:
20
LoRa'" technology;
Sigfox'" technology;
WM-BUS technology.
Thus, the digital radio modem according to the proposed technique is particularly
appropriate in the context of the development of the Internet of Things, i.e. for the deployment of
wireless communication networks based upon optimized communication protocols for the
minimization of the electrical consumption of sensors and other communicating objects employed.
In another particular form of embodiment of the proposed technique, this preselected
25 radio access technology is selected from a series of predefined radio access technologies within
said digital radio modem.
In this manner, a single digital radio modem can accommodate different radio access
technologies, and can thus be employed differently in different contexts by means of a simple
configuration step. Specifically, this permits the optimization of manufacturing costs, and facilitates
30 the installation of these devices.
According to a second aspect, the proposed technique relates to an analog radio interface
module, which comprises a protective frame, connection means to at least one antenna, and at
6
least one third communication interface with a digital radio modem as described above, wherein
said connection means to at least one antenna and said at least one third communication interface
are arranged within said frame.
Thus, the analog radio interface module is not integrated, for example, in a printed circuit:
5 it has a dedicated frame, within which at least one communication interface with a digital radio
modem according to the proposed technique is arranged. In this manner, the analog radio interface
module according to the proposed technique constitutes an independent physical block, thus
providing a manifest degree of flexibility in its use: it can easily be disconnected and reconnected
to one or more digital radio modems. It further comprises connection means to at least one
I 0 antenna, thereby rendering it suitable for the management of different antennae configurations.
According to a further aspect, the proposed technique relates to a radio interface device
for the reception and transmission of data from and to at least one wireless sensor, which
comprises at least one digital radio modem of the type described above, and an analog radio
interface module of the type described above. The analog radio interface module ls connected to
15 said at least one digital radio modem by the cooperation of the second and third communication
interfaces thereof.
In this manner, it is possible to constitute a radio interface device by the combination of
one or more digital radio modems of the same type (employing the same radio access technology)
with an analog radio interface module according to the proposed technique. The fact that these
20 different physical blocks each has a dedicated frame, comprising complementary communication
interfaces, provides a solution with a high degree of modularity. It is thus possible to achieve a very
simple adaptation to a large number of situations, by the simple choice of one type of digital radio
modem and one type of analog radio interface module to be combined. Selection of the type of
digital radio modem thus permits the definition of the radio access technology to be employed
25 (depending upon the functionalities provided by this digital radio modem, a simple software
configuration may be sufficient). Selection of the type of analog radio interface module permits the
definition, firstly of the frequency band which is to be employed for radio transmission, and
secondly of the antennae configuration typology to be used (sectorized, polarized or
omnidirectional antenna, etc.).
30 In a particular form of embodiment, a radio interface device of this type comprises a
plurality of digital radio modems according to the proposed technique, associated with the same
radio access technology, wherein the digital radio modems constituting said plurality of digital radio
7
modems are mutually connected by means of their first communication interfaces.
It is thus possible to undertake the easy mutual connection of a plurality of digital radio
modems of the same type according to the proposed technique, and to associate the combination
thus formed with a single analog radio interface module. In this manner, it is possible to increase
5 the load capacity of a radio interface device, by the simple addition of a supplementary digital radio
modem to the existing installation: the solution according to the proposed technique thus permits,
for example, a very simple response to an expansion in the number of wireless sensors to be
managed within a given territory, under the coverage of a single antenna.
According to a further aspect, the proposed technique relates to a gateway for the
10 interconnection of at least one wireless sensor network with at least one wide-area communication
network, wherein said gateway is characterized in that it comprises:
at least one radio interface device according to the proposed technique;
at least one complementary interface device with said at least one wide-area
communication network, wherein said complementary device comprises at least a fourth
15 communication interface, wherein said complementary device is connected to said at least one
radio interface device by means of the cooperation of said fourth communication interface with a
first communication interface on a digital radio modem of said radio interface device.
In this manner, it is possible to construct a gateway which permits the interconnection of
at least one wireless sensor network with at least one other wide-area communication network, by
20 the simple combination of radio interface devices (themselves obtained by the simple combination
of digital radio modems with analog radio interface modules), wherein at least one compatible
complementary device manages access to the wide-area network. The communication interfaces
which are simultaneously present on the complementary devices and on the digital radio modems
which are incorporated within the radio interface devices permit the interconnection of all these
25 elements, by the constitution of a common data bus, for example of the SPI type. Other types of
complementary devices, also provided with compatible communication interfaces, can also permit
access to this shared data bus, thereby finalizing the constitution of the gateway: by way of an
example, reference may be made to a complementary device for the delivery of an electric power
supply to the entire gateway, or a complementary control device for the monitoring of the
30 operation of all the other complementary devices and radio interface devices included in the
gateway, and for the control of data exchanges executed between all these different elements.
In a particular form of embodiment, a gateway of this type comprises a plurality of radio
8
interface devices according to the proposed technique, wherein said radio interface devices of said
plurality of radio interface devices are mutually connected by means of the cooperation of the first
communication interfaces of the digital radio modems of said plurality of radio interface devices.
Thus, a first gateway can comprise a string of a plurality of radio interface devices according
5 to the proposed technique, and thus be adaptable to an even greater number of situations. In this
manner, for example, it is possible to combine radio interface devices based upon heterogeneous
radio access technologies in a single gateway. This flexibility of connection also permits the
constitution of a gateway which is capable of managing several different frequency bands. This also
permits the deployment of sectorization, for example, in the interests of superior territorial
10 coverage. Naturally, all these examples are provided exclusively by way of illustration, and not by
way of limitation, and a person skilled in the art will be aware of the multiple configuration options
provided by a gateway which is constituted according to the proposed technique.
The different forms of embodiment described above are mutually combinable for the
deployment of the invention.
15 4. List offigures
20
25
30
Further characteristics and advantages of the invention will be clarified by the following
description of a preferred form of embodiment of the invention, which is provided by way of
illustration only and not by way of limitation, and by the attached drawings, in which:
figure 1 shows a simplified view of the main modules in a gateway for the deployment of a
wireless sensor network;
figures 2a and 2b show different views of a digital radio modem, in a particular form of
embodiment of the proposed technique;
figures 3a and 3b show different views of an analog radio interface module, in a particular
form of embodiment of the proposed technique;
figures 3c and 3d show different views of an analog radio interface module, in another
particular form of embodiment of the proposed technique;
figure 4a illustrates an example of the fitting in progress of an analog radio interface module
to a digital radio modem, thus constituting a radio interface device, according to a particular
form of embodiment of the proposed technique;
figure 4b illustrates an example of the fitting of an analog radio interface module to a block
of a plurality of interconnected digital radio modems, thus constituting a radio interface
device, according to another particular form of embodiment of the proposed technique;
5
9
figures Sa to Sc show different examples of gateways for the deployment of a wireless
sensor network, obtained by the combination of digital radio modems, complementary
devices and analog radio interface modules according to the proposed technique, in a
particular form of embodiment.
5. Detailed description
The proposed technique relates to a novel base station architecture for the deployment of
sensor networks, or other communicating objects, in a wireless arrangement. Throughout the
document, a base station of this type is also described as a "gateway", and the term "wireless
sensor network" is employed indiscriminately to signify a network of wireless sensors, or a network
I 0 of- potentially more complex -wireless communication objects. The proposed architecture is
based upon the separation of the key conventional functionalities of a gateway into different
physical blocks, each of which has its own dedicated frame, within which different communication
interfaces are arranged, such that these different physical blocks are interconnectable. This design
not only permits the simple and rapid construction of "customized" gateways, thus perm·ltting the
15 fulfilment of many different types of requirements, but also endows these gateways with a high
level of modularity and scalability. The proposed architecture permits the highly straightforward
replacement of one physical block by another, or the addition of a further physical block to a
gateway already constituted. To this end, this architecture is particularly appropriate for the
deployment of large-scale wireless sensor networks (although it can also be employed in the
20 context of the deployment of wireless sensor networks on a smaller scale).
25
5.1. Description of the constituent elements of a gateway
With reference to figure 1, a simplified schematic view is represented of the main modules
deployed in a gateway for a wireless sensor network. A gateway (100) of this type comprises:
a first interface module (110) with the wireless sensor network;
at least one second interface module (120) with another network, for example a local IP
network, or a wide-area network such as the Internet;
a control module {130), which is designed to control the abovementioned interface
modules.
The first interface module {110) with the wireless sensor network constitutes the radio
30 access device of the gateway. It is designed to execute data exchanges between the gateway and
the wireless sensors, via a radio transmission channel. It comprises the following main submodules:
5
10
10
an antenna (111), which is designed to radiate or capture radio waves for the conveyance
of data to be exchanged;
an analog radio interface module (112), which constitutes the front-end analog radio
frequency system, responsible for the execution of processing functions on the analog
signal delivered by or supplied to the antenna, in the frequency band which is employed for
radio transmission (these processing functions may involve filtering, frequency
transposition, power amplification, etc.); the analog radio interface module also executes
analog-to-digital conversion functions (upon the reception of data from sensors) and
digital-to-analog conversion functions (upon the transmission of data to sensors);
a digital radio modem (113) which specifically permits the modulation and demodulation
of digital signals, according to the radio access technology employed, for example by means
of a digital signal processor (DSP).
In the majority of existing gateways for wireless sensor networks, these elements are
generally embodied by electronic circuits which are present on the same electronic circuit board,
15 or are at least integrated in the same frame (with the exception of the antenna, which is either
secured to said frame, or is connected to said frame by means of a dedicated connector arranged
within said frame). This advanced integration is such that these gateways are appropriate for the
fulfilment of highly specific requirements (for the use of a given radio access technology, within a
given frequency band), but do not fulfill the requirements for adaptability and scalability associated
20 with the deployment of large-scale wireless sensor networks.
5.2. General principle of the proposed technique
The technique described here endeavors to at least partly rectify this problem, firstly by the
physical separation, in separate frames (or housings) of the analog module (i.e. the analog radio
interface module which constitutes the front-end analog system) and the digital module (i.e. the
25 digital radio modem) of a radio interface device; and secondly by the deployment of means for the
simple connection of a plurality of radio interface devices, not only to one another, but also to
complementary devices such as control devices or interface devices with a wide-area network. The
general principle of the proposed technique therefore involves the isolation of the main modules
deployed in a gateway for a wireless sensor network into independent physical blocks, which can
30 be mutually combined. By this technique, it is therefore possible to deploy modular and scalable
gateways for wireless sensor networks, which can be rapidly and easily configured or adapted to
respond to any type of situation, by the simple replacement of existing physical blocks or the
addition of new physical blocks.
5.3. Digital radio modem
11
To this end, a device for the modulation and demodulation of a digital signal (also described
in the remainder of this document as a digital radio modem) is proposed, according to a first aspect
5 of the technique described. This digital radio modem is configured to operate using a preselected
radio access technology, for example LoRa'M, Sigfox'M or WM-Bus technology, all of which
technologies are particularly appropriate for the deployment of wireless sensor networks. The
modem comprises a frame, which protects the electronics required for its operation, and thus
constitutes an independent physical block. A plurality of communication interfaces are arranged
10 within said frame, thus permitting the very simple connection or disconnection of the digital radio
modem to or from the remainder of a system. Here, and in the remainder of the document, the
term "communication interfaces" is understood to include interfaces of a physical type which are
employed for the mutual physical interconnection of a plurality of electronic devices. These
communication interfaces can, for example, assume the form of serial connectors (such as SPI
15 (serial peripheral interface) connectors) which permit the constitution of a common data bus which
is shared between all the devices thus interconnected.
20
In a particular form of embodiment of the proposed technique, the digital radio modem
comprises at least a first communication interface with a complementary device, and at least a
second communication interface with an analog radio interface module.
The first communication interface present on the digital radio modem permits the
connection thereof to a complementary device, which may be a device of the same type (namely,
another digital radio modem according to the proposed technique), or a device of anothertype (for
example a control device, an electric power supply device, or a device for the management of
another type of interface- for example Ethernet, WiFi, or 3G/4G- with another network). In the
25 first case, the digital radio modems are mutually connected by the cooperation of the first
communication interfaces which are respectively present on each of said devices. In the second
case, the complementary device to which the digital radio modem is connected is a "compatible"
device, in that the device itself comprises at least one communication interface which permits the
cooperation thereof with a first communication interface on the digital radio modem according to
30 the proposed technique. These communication interfaces can, for example, assume the form of SPI
connectors, and thus contribute to the constitution of a common data bus which is shared by the
devices, once the latter are connected.
12
The second communication interface present on the digital radio modem permits the
connection thereof to a compatible analog radio interface module, as described hereinafter in the
present document. In this manner, it is possible to constitute a radio interface device which, by the
simple addition of one or more antennae, permits the reception and transmission of data from or
5 to at least one remote wireless sensor. By way of an example, this second communication interface
can also assume the form of an SPI connector.
In a particular form of embodiment of the proposed technique, the digital radio modem
comprises at least two first communication interfaces with a complementary device, thus
permitting the communication thereof with at least two complementary devices. These
10 communication interfaces are respectively situated at the termination of at least one data bus, thus
permitting said digital radio modem to exchange data with the complementary devices. In this
manner, a single digital radio modem can be connected to a plurality of complementary devices,
which can be other devices of the same type (i.e. other digital radio modems according to the
proposed technique) or other compatible devices. It is thus possible to constitute a string of
15 multiple devices, such that the latter all share at least one common data bus (for example, an SPI
bus), thus permitting the mutual exchange of data between all the devices thus interconnected.
Preferably, the "compatible" complementary devices (other than digital radio modems) also
comprise at least two communication interfaces which are designed to cooperate with the first
communication interfaces of a digital radio modem according to the proposed technique, such that
20 it is possible to interconnect the various devices in any order.
In another particular form of embodiment of the proposed technique, the radio access
technology deployed in the digital radio modem can be selected, in terms of software, from a group
of predefined radio access technologies (i.e. pre-parameterized, pre-registered or accessible) in
said digital radio modem. The digital radio modem thus incorporates sufficient on-board electronics
25 for the management of a number of types of digital modulation and demodulation; in software
terms, it is possible to configure the type thereof which is to be employed. In this manner, a single
digital radio modem can accommodate different radio access technologies, and can thus be
employed differently in different contexts. This may also permit the optimization of production
costs for these devices.
30 5.4. Analog radio interface module
According to a further aspect, the proposed technique also relates to an analog radio
interface module. This module- which serves as the front-end analog system for adaptation to the
13
frequency band employed for radio transmission- is designed for use in conjunction with at least
one digital radio modem according to the proposed technique. It comprises a frame, which
incorporates the requisite electronics for its operation, and thus constitutes an independent
physical block. It also comprises, arranged within said frame, connection means to at least one
5 antenna, and at least one third communication interface with a digital radio modem, of the type
described above.
The function of this analog radio interface module is the management of adaptation to the
frequency band employed for radio transmission, and to provide the necessary connectivity for the
accommodation of different types of antennae (omnidirectional, polarized or sectorized).
10 Moreover, depending upon the different particular forms of embodiment of an analog radio
interface module according to the proposed technique, the frequency band accommodated by this
module, the number of third communication interfaces and the type of connection means to the at
least one available antenna may vary. The proposed technique thus provides access to an extensive
range of analog interface modules, configured in the form of independent physical blocks, which
15 can cooperate with one or more digital radio modems, in order to permit the coverage of any type
of situation, in terms of both frequency bands and the type of antennae to be employed.
5.5. Radio interface device
According to a further aspect, the proposed technique also relates to a radio interface
device for the reception and transmission of data from and to at least one wireless sensor. A radio
20 interface device of this type comprises the following:
25
at least one digital radio modem according to the proposed technique;
an analog radio interface module according to the proposed technique.
The analog radio interface module is connected to said at least one digital radio modem by
means of the cooperation of said second and third communication interfaces.
It is thus possible to constitute a radio interface device by the combination of at least one
digital radio modem with an analog radio interface module according to the proposed technique.
The fact that each of these elements has a dedicated frame, incorporating complementary
communication interfaces, permits the achievement of a highly modular solution. A straightforward
adaptation to a large number of situations is thus possible, by the simple selection of physical blocks
30 to be combined, namely, the selection of a digital radio modem and the selection of an analog radio
interface module to be combined. Selection of the digital radio modem thus permits the definition
of the radio access technology to be employed (depending upon the functionalities provided by this
14
digital radio modem, a simple software configuration may be sufficient). Selection of the analog
radio interface module permits the definition, firstly of the frequency band which is to be employed
for radio transmission, and secondly of the type of antennae configuration to be employed
(sectorized, polarized or omnidirectional antenna, etc.).
5 In a particular form of embodiment of the proposed technique, the radio interface device
comprises a plurality of digital radio modems according to the technique described. In this case,
these digital radio modems are all of the same type (employing the same radio access technology),
and are mutually connected by means of their first communication interfaces. It is therefore
straightforward to undertake the constitution or scaling of a radio interface device, such that it is
10 consistently dimensioned to respond to an expansion in the number of wireless sensors to be
managed within a given territory, which is covered by the same antenna. In practice, the proposed
technique permits the simple mutual connection of a plurality of digital radio modems, and the
association of the unit thus formed with a single analog radio interface module. In this manner, it
is possible to increase the load capacity of a radio interface device, by the simple addition of a
15 supplementary digital radio modem to an existing installation.
5.6. Gateway for wireless sensor networks
The proposed technique also relates to a gateway for wireless sensor networks. This
gateway specifically permits the interconnection of at least one wireless sensor network with at
least one other wide-area communication network and, to this end, comprises at least one radio
20 interface device of the type described above, for the exchange of data with said wireless sensors,
and at least one complementary interface device with a wide-area communication network. The
complementary device is a compatible device of the type already introduced in the present
document, and thus comprises at least one communication interface for the connection thereof to
a first available communication interface on a digital radio modem which is incorporated in the
25 radio interface device. Other types of complementary devices, which are likewise provided with
compatible communication interfaces, can also be integrated in the gateway: by way of an example,
reference may be made to a complementary device for the delivery of an electric power supply to
the entire gateway, or a complementary control device for the monitoring of the operation of all
the other complementary devices and radio interface devices included in the gateway, and for the
30 control of data exchanges executed between all these different elements.
In a particular form of embodiment, a single gateway according to the proposed technique
can comprise a plurality of radio interface devices, which are mutually connected by means of the
15
cooperation of the first communication interfaces available within digital radio modems which are
incorporated in each radio interface device. In this manner, it is possible, for example, to combine
radio interface devices based upon heterogeneous radio access technologies in a single gateway.
This flexibility of connection also permits the constitution of a gateway which is capable of
5 managing different frequency bands. This also permits the deployment of sectorization, for
example, in the interests of superiorterritorial coverage. Naturally, all these examples are provided
exclusively by way of illustration, and not by way of limitation, and a person skilled in the art will be
aware of the multiple configuration options provided by a gateway which is constituted according
to the proposed technique.
10 5.7. Description of a particular form of embodiment of the proposed technique
With reference to the series of figures 2 to 5, an exemplary implementation ofthe proposed
technique is described, which permits the achievement of the objective of a modular and scalable
gateway which is capable of providing a response to the issues raised by the deployment of largescale
wireless sensor networks.
15 5. 7.1 Digital radio modem
With reference to figures 2a and Zb, different views are presented of a digital radio modem
(200) according to a particular form of embodiment of the proposed technique. In this example,
which is provided exclusively by way of illustration and not by way of limitation, this digital radio
modem (200) incorporates a protective frame (201) of an overall parallelepipedic design,
20 comprising the following:
25
on one of its surfaces, described as the "upper surface" (202), two male SPI connectors
(203, 203');
on the opposing surface to said upper surface, described as the "lower surface" (204), two
female SPI connectors (205, 205'), which are designed to cooperate with the two male SPI
connectors (203, 203') of another digital radio modem according to the form of
embodiment described, when these devices are connected.
The male SPI connectors (203, 203') and female SPI connectors (205, 205') form the
respective terminations of at least one SPI (serial peripheral interface) data bus, arranged internally
to the frame, which is employed by the digital radio modem for the transmission and reception of
30 data to and from other complementary devices (which may specifically be other digital radio
modems according to the particular form of embodiment described herein).
The frame moreover comprises, on one of its lateral surfaces, described as the "rear
5
16
surface" (206), at least one further SPI connector (207) and at least one coaxial connector (208).
These connectors are designed to cooperate with complementary connectors which are present on
an analog radio interface module, as described hereinafter.
5. 7.2 Analog radio interface module
With reference to figures 3a to 3d, we will now present two examples of analog radio
interface modules which are designed to cooperate with one or more digital radio modems
according to the particular form of embodiment described.
Figures 3a and 3b illustrate different views of a first example of an analog radio interface
module (300) which is designed to cooperate with a digital radio modem, according to a particular
10 form of embodiment of the proposed technique. In this example, which is provided exclusively by
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way of illustration and not by way of limitation, this module (300) incorporates a protective frame
(301) of generally parallelepipedic design, and comprises the following:
on one of its surfaces, described as the "rear surface" (302), at least one coaxial connector
(303) which is designed for the connection of at least one antenna.
on the opposing surface to said rear surface, described as the "front surface" (304), at least
one SPI connector (305) and at least one coaxial connector (306), wherein these connectors
(305, 306) are designed to cooperate respectively with the respective complementary
connectors which are present on the rear surface of a digital radio modem of the type
described above.
This analog radio interface module (300) is dimensioned and configured such that, once
connected to the digital radio modem according to the particular form of embodiment illustrated
here, the unit formed by these two elements constitutes a consolidated block of overall
parallelepipedic shape. To this end, the front surface (304) of the analog radio interface module is
of substantially equivalent dimensions to the rear surface of the digital radio modem.
With reference to figures 3c and 3d, a further example is presented of an analog radio
interface module which is appropriate for use in the context of the particular form of embodiment
of the proposed technique described here. In this particular form of embodiment, the analog radio
interface module (300') is designed to cooperate, no longer with a single digital radio modem, but
with a plurality of digital radio modems (four, in the example illustrated). The protective frame
30 (301') of this module is of an overall parallelepipedic shape, and its front surface (304') is of
substantially equivalent dimensions to the four rear surfaces of the digital radio modems arranged
side by side. This module is dimensioned and configured such that, once connected to a block of
17
four digital radio modems, the unit formed by all these elements constitutes a consolidated block
of overall parallelepipedic shape. The analog radio interface module incorporates, on its rear
surface, at least one coaxial connector, which is designed for the connection of at least one antenna
and, on its front surface, at least one connector which is designed to cooperate with at least one
5 respective complementary connector which is present on the rear surface of at least one of the
digital radio modems to which said module is connected.
These examples are provided exclusively by way of illustration and not by way of limitation,
and other types of analog radio interface modules, which are configured and dimensioned for
connection to a different number of digital radio modems, may also be deployed in the context of
10 the proposed technique (for example, an analog radio interface module which cooperates with two
interconnected digital radio modems, or an analog radio interface module which cooperates with
four interconnected digital radio modems). In the interests of simplification, an "analog radio
interface module of dimension N" is defined as an analog radio interface module which is specially
designed for the simultaneous connection to a number N of interconnected digital radio modems.
15 In a particular form of embodiment of the proposed technique, the frame of an analog radio
interface module of dimension N is dimensioned and configured such that its front surface is of
dimensions which are substantially equivalent to those of N rear surfaces of digital radio modems
arranged side by side. This permits the retention of the overall parallelepipedic shape of radio
interface devices, even when a single analog radio interface module is connected to a plurality of
20 digital radio modems.
5. 7.3 Radio interface device
Figures 4a and 4b illustrate two examples of assemblies of an analog radio interface module
with at least one digital radio modem according to the proposed technique, in order to constitute
a radio interface device for the reception and transmission of data from and to at least one wireless
25 sensor. Figure 4a thus represents the connection of an analog radio interface module of dimension
one to a single digital radio modem. Figure 4b represents the connection of an analog radio
interface module of dimension three to a block comprising three digital radio modems which are
interconnected by means of male and female SPI connectors which are present on their upper and
lower surfaces. In the case of the connection of a single analog radio interface module to a plurality
30 of interconnected digital radio modems, as illustrated in figure 4b, these various digital radio
modems are all of the same type, i.e. they employ a single radio access technology. The remaining
available coaxial connectors on the rear surface of the analog radio interface module are employed
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for the connection of at least one antenna. The remaining available SPI connectors (402, 402') on
either side of the radio interface device thus constituted are employed for the connection of this
radio interface device to other radio interface devices, or to other compatible complementary
devices (such as control devices, or interface devices to other networks, for example to the
5 Internet).
A radio interface device thus constituted can therefore accommodate a given radio access
technology in a given frequency band. It is also possible to describe this device by a dimension,
corresponding to its constituent number of digital radio modems (analogously to the definition
applied in conjunction with the analog radio interface module). Thus, in the context of the present
10 document, a LoRa'" 868MHz radio interface device of dimension 3 is a radio interface device
constituted by the combination of three digital radio modems employing LoRa'" radio access
technology, associated with a single analog radio interface module operating in the 868MHz
frequency band. The dimension is an indicator of the load (in terms of the number of wireless
sensors) which a radio interface device is capable of managing.
15 5.7.4 Examples of gateway configurations
With reference to figures Sa to Sc, various gateway configurations are presented, provided
exclusively by way of illustration and not by way of limitation, which can be deployed in a highly
simple manner using the proposed technique.
These configurations involve other complementary devices, in addition to digital radio
20 modems and their associated analog radio interface modules. These may be mandatory or optional
complementary devices for the constitution of a gateway architecture. Thus, in one particular form
of embodiment represented by the example associated with figure Sa, a gateway (500} according
to the proposed technique comprises a complementary control device (501) which is designed,
firstly to deliver the electric power supply to the entire gateway, wherein this device is connected,
25 for example, to a conventional electric power socket, or is supplied directly via an Ethernet cable
using PoE (Power over Ethernet) technology, and secondly to control all the other complementary
devices and radio interface devices. Complementary interface devices (502), permitting different
types of interconnection (Ethernet, WiFi, 3G/4G, etc.) with other local or wide-area networks, can
also be deployed. In the particular form of embodiment described here, each of these
30 complementary devices comprises a protective frame of dimensions which are substantially
equivalent to those of a digital radio modem according to the proposed technique. In common with
the frames of digital radio modems, these frames respectively comprise, on their upper and lower
19
surfaces, at least one male SPI connector and at least one female SPI connector, which are designed
to cooperate with the SPI connectors on another device, where these devices are combined. These
male and female SPI connectors form the respective terminations of at least one data bus, which is
arranged internally to the frame. Thus, the cooperation of the various SPI connectors, when a
5 plurality of devices are mutually combined, permits all the devices thus interconnected to
communicate with each other by means of the common communication bus thus established.
Figure Sa shows an example of a gateway comprising four radio interface devices (503a,
503b, 503c, 503d) for the reception and transmission of data from and to wireless sensors, wherein
each of these radio interface devices comprises a single digital radio modem, each associated with
10 a single analog radio interface module. The radio interface device (503d) is constituted, for
example, by the combination of the digital radio modem (505) with the analog radio interface
module (504). A configuration of this type can comprise, for example, three radio interface devices
accommodating the LoRa radio access technology in the 868MHz frequency band, each of which is
associated with a sectorized antenna (tri-sectorization), and a radio interface device for the
15 accommodation of WM-Bus radio access technology in the 169M Hz frequency band, associated
with an omnidirectional antenna. In this manner, the gateway thus constituted is capable of
accommodating two types of radio access technologies, one (LoRa'") for communication with
connected objects, and the other (WM-Bus) for communication with electricity or gas meters, e.g.
for the execution of remote readings. If LoRa'" technology is to be operated in another frequency
20 band, for example in the event of the transposition of an existing solution to a territory in which
different radio communication regulations are in force, the gateway can be very easily adapted to
this new situation, simply by replacing the three analog radio interface modules which are
configured for the 868MHz band with three others which are configured for the desired frequency
band, for example the 915MHz band. If, in another example, LoRa'" technology is to be operated
25 in the 433MHz frequency band and, for any reason, it is preferred that a single omnidirectional
antenna should be employed rather than three sectorized antennae, the three analog radio
interface modules which are configured for the 868MHz band can be very simply replaced by a
single analog radio interface module of dimension three, configured for the 433MHz band. This
gateway configuration is illustrated in figure Sb, which shows an example of a gateway comprising
30 two radio interface devices for the reception and transmission of data from and to wireless sensors:
a first radio interface device comprising three digital radio modems associated with the same
analog radio interface module, and a second radio interface device, wherein this radio interface
20
device comprises a single digital radio modem associated with a single analog radio interface
module.
Finally, figure Sc shows an example of a gateway comprising a single radio interface device
for the reception and transmission of data from and to wireless sensors, wherein this radio interface
5 device itself comprises four digital radio modems associated with a single analog radio interface
module. This radio interface device is associated, for example, with an omnidirectional antenna. In
this case, the gateway manages only a single radio access technology, but the multiplicity of digital
radio modems is such that it is capable of managing a large number of sensors.
It should observed that, while the gateways presented in figures Sa to Sc all comprise four
10 digital radio modems (divided between a variable number of radio interface devices), these are only
examples provided exclusively by way of illustration and not by way of limitation: a gateway
according to the proposed technique comprises one or more digital radio modems and one or more
analog radio interface modules, wherein one digital radio modem is always coupled to a single
analog radio interface module, but a single analog radio interface module can be associated with a
15 number of digital radio modems.
In consideration of these examples, a person skilled in the art will easily appreciate the
potential offered by the proposed technique, in terms of both modularity and scalability. The
possibility of the very straightforward combination of digital radio modems with an analog radio
interface module to constitute a radio interface device, added to the possibility ofthe combination
20 of a plurality of radio interface devices thus constituted within the same gateway, offer an elegant
solution to the various potential issues arising in conjunction with the deployment or maintenance
of large-scale wireless sensor networks. This modular gateway architecture can accommodate the
diversity of radio access technologies, both existing and forthcoming, together with the diversity of
frequencies employed for radio transmission, different types of antennae and adaptation to the
25 number of sensors to be addressed.
30
By way of examples, the instances of application set out below demonstrate the potential
responses delivered by the proposed technique to various situations which may arise in conjunction
with the deployment of large-scale sensor networks:
The requirement for the simultaneous accommodation of a plurality of wireless sensor
networks based upon different protocols (for example, a LoRa'" network and a WM-Bus
network): using the proposed technique, a multi-technology radio access carrier medium
can easily be achieved by the simple combination of at least one radio interface device
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which is adapted to each radio access technology to be accommodated (for example, the
combination within the gateway of a radio interface device comprising one or more LoRa'M
digital radio modems, and a radio interface device comprising one or more WM-Bus digital
radio modems).
The requirement for the management of multiple frequency bands for radio transmission,
using the same radio access technology (for example, the simultaneous accommodation of
LoRa'M technology in the 433MHz and 868MHz bands): using the proposed technique, the
accommodation of multiple bands is easily achieved by the combination of at least one
radio interface device which is adapted to each frequency band to be managed (for
example, by the combination within the gateway of a LoRa'M radio interface device
comprising a 433MHz analog radio interface module, and a LoRa'M radio interface device
comprising a 868MHz analog radio interface module).
The requirement for the transition from an omnidirectional antenna to a tri-sectorized
three-antenna configuration (and vice versa): using the proposed technique, sectorization
can be deployed simply, by the combination of a radio interface device of the same type
(employing the same radio access technology and the same frequency band) for each sector
to be covered, wherein each of these radio interface devices is connected to a dedicated
sectorized antenna (for example, a combination of three Sigfox 915MHz radio interface
devices of dimension one). Conversely, the transition from a tri-sectorized configuration to
a single-antenna configuration (omnidirectional antenna) can also be executed very simply,
for example by replacing the analog radio interface modules of dimension one associated
with the radio interface device for each sector with a single analog radio interface module
of dimension three, to which the omnidirectional antenna will be connected (thus
switching, for example, from a configuration with three Sigfox 915MHz radio interface
devices of dimension one to a configuration with a single Sigfox 915MHz radio interface
device of dimension three).
The requirement for the modification of the load (in terms of the number of sensors) which
can be accommodated by a radio interface device: using the proposed technique, an
adjustment of capacity can be deployed simply by replacing the targeted radio interface
device with a radio interface device of the same type (employing the same radio access
technology and the same frequency band), but of smaller dimensions (if fewer sensors are
to be managed) or larger dimensions (if more sensors are to be managed).
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The requirement for the management of a new type of connection to another wide-area
network (for example, the management of a WiFi link): using the proposed technique, the
scalability of options for the connectivity of a gateway can be easily achieved, by the simple
addition or replacement of a compatible complementary device.
These examples are provided exclusively by way of illustration and not by way of limitation,
and it will be clearly apparent to a person skilled in the art that the proposed technique can provide
an appropriate response to numerous situations, including complex situations in which it is
necessary to undertake the simultaneous adaptation of multiple parameters (modification of the
radio access technology, concomitantly with a modification of the frequency band and the type of
I 0 antennae to be employed, and a modification of the number of sensors to be managed, for
example).
5.7.5. Further characteristics and advantages
Further significant characteristics are described here, with reference to the gateway
architecture presented according to the particular form of embodiment illustrated by figures 2 to
15 5.
It may be interesting to note, for example, that no external cable is necessary for the
connection of the various constituent physical blocks of the gateway (digital radio modems,
associated analog radio interface modules, complementary devices): the frames of these various
devices are configured and dimensioned to permit the assembly thereof by the interlocking of the
20 various respective complementary connectors which are present on their various surfaces, wherein
the final assembly assumes a compact and overall parallelepipedic form, which simplifies its
installation and integration in any type of environment.
The various frames deployed also incorporate, in certain particular forms of embodiment,
characteristics which are intended to ensure the effective mutual attachment of the constituent
25 blocks of a gateway according to the proposed technique, specifically for the prevention of any
unintentional disconnection of these blocks.
Accordingly, digital radio modems and analog radio interface modules are provided with
complementary means of attachment. For example, the frame of a digital radio modem may
incorporate one or more threaded holes, which are designed to accommodate complementary
30 wing screws which pass through the frame of an associated analog radio interface module.
Digital radio modems also incorporate means which contribute to their mutual attachment,
or the attachment thereof to complementary devices. These means can assume, for example, the
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form of a protrusion on the frame of said devices, in which a hole is formed, such that all the holes
thus constituted are mutually aligned, once the various constituent devices of the gateway are
interlocked. These holes may then permit the passage of various means of attachment (threaded
rods and fixings, collars, etc.).
The frames of digital radio modems and complementary devices incorporate means for the
attachment of a gateway for wireless sensor networks constituted according to the proposed
technique in a cabinet or in a conventional protective bay.
In a particular form of embodiment of the proposed technique, the frame of the different
constituent physical blocks of the gateway, and specifically the frame of the analog radio interface
10 modules, is moreover designed to function as a Faraday cage, in order to protect these modules
from any electromagnetic disturbances to which they may be exposed. In another form of
embodiment, a plate which functions as a protective shield, and which assumes this function of a
Faraday cage, can be secured as a cover for the analog radio interface modules.

CLAIMS
1. A digital radio modem (200) for the modulation and demodulation of a digital signal, in
accordance with a preselected radio access technology, wherein said digital radio modem
is characterized in that it comprises a protective frame (201) of overall parallelepipedic
design and a plurality of communication interfaces which are arranged within said
protective frame (201),
wherein the plurality of communication interfaces comprises:
at least two first communication interfaces with a complementary device,
wherein one of the first communication interfaces comprises:
on one of the surfaces of the protective frame (201), described as the "upper
surface" (202), two male SPI connectors (203, 203');
wherein another of the first communication interfaces comprises:
on the opposing surface of the protective frame (201) to said upper surface (202),
described as the "lower surface" (204), two female SPI connectors (205, 205'), which are
designed to cooperate with the two male SPI connectors (203, 203') of another digital radio
modem such that, when a plurality of digital radio modems are connected: the male (203,
203') and female (205, 205') SPI connectors constitute the respective terminations of at
least one SPI data bus, arranged internally to the protective frame (201), and employed by
the digital radio modem for the transmission and reception of data to and from the digital
radio modem(s) to which it is connected;
at least one second communication interface with an analog radio interface module,
wherein the second communication interface comprises:
on one of the lateral surfaces of the protective frame (201), described as the "rear
surface" (206), at least one other SPI connector (207) and at least one coaxial connector
(208), which are designed to cooperate with the complementary connectors present on an
analog radio interface module.
The digital radio modem as claimed in claim 1, characterized in that said preselected radio
access technology is selected from a series of predefined radio access technologies within
said digital radio modem.
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3. The digital radio modem as claimed in one of the preceding claims, having complementary
means of attachment to the means of attachment of said analog radio interface module.
4.
5.
6.
7.
The digital radio modem as claimed in the preceding claim, wherein the protective frame
(201) of the digital radio modem incorporates one or more threaded holes, which are
designed to accommodate complementary wing screws which pass through the protective
frame (201) of said associated analog radio interface module.
The digital radio modem as claimed in one of the preceding claims, wherein the digital radio
modem incorporates means which contribute to the attachment thereof to other digital
radio modems, or to complementary devices.
The digital radio modem as claimed in the preceding claim, wherein the means which
contribute to the attachment of the digital radio modem to other digital radio modems or
to complementary devices comprise a protrusion on the protective frame (201) of the
digital radio modem, in which a hole is formed, such that the hole thus formed is aligned
with the holes formed in said other digital radio modems or in said complementary devices,
once the various devices are interlocked.
An analog radio interface module (300), characterized in that it comprises a protective
frame (301) of overall parallelepipedic design, connection means to at least one antenna,
and at least one third communication interface with a digital radio modem as claimed in
any one of claims 1 to 6, wherein said connection means to the at least one antenna and
said at least one third communication interface are arranged within said protective frame
(301),
wherein the connection means to the at least one antenna comprise:
-on one of the surfaces of the protective frame (301), described as the "rear surface" (302),
at least one coaxial connector (303), which is designed for the connection of the at least
one antenna,
30 wherein the third communication interface with a digital radio modem comprises:
-on an opposing surface of the protective frame (301) to said rear surface, described as the
"front surface" (304), at least one SPI connector (305) and at least one coaxial connector
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(306), wherein these connectors (305, 306) are designed to cooperate respectively with the
respective complementary connectors which are arranged on a rear surface of a digital
radio modem according to one of claims 1 to 6,
wherein the protective frame (301) of the analog radio interface module is dimensioned and
configured such that the front surface thereof is of substantially equivalent dimensions to
theN rear surfaces of digital radio modems which are designed to be arranged side by side,
where N is a whole number greater than or equal to 1.
8.
9.
The analog radio interface module (300) as claimed in claim 7, configured for connection to
a digital radio modem as claimed in one of claims 1 to 6, wherein the front surface (304) of
the protective frame (301) of the analog radio interface module is of substantially
equivalent dimensions to the rear surface of said digital radio modem.
The analog radio interface module (300} as claimed in claim 7, configured for simultaneous
connection to a number N of digital radio modems as claimed in one of claims 1 to 6,
wherein the digital radio modems are designed to be arranged side by side and
interconnected, wherein the front surface (304) of the protective frame (301) ofthe analog
radio interface module is of substantially equivalent dimensions to the N rear surfaces of
said digital radio modems.
10. The analog radio interface module (300} as claimed in one of claims 7 to 9, wherein the
protective frame (301) of the analog radio interface module is designed such that it
functions as a Faraday cage.
11. A radio interface device fort he reception and transmission of data from and to at least one
wireless sensor, wherein said device is characterized in that it comprises:
at least one digital radio modem as claimed in any one of claims 1 to 6;
an analog radio interface module as claimed in one of claims 7 to 10, connected to
said at least one digital radio modem by means of the cooperation of said second and third
communication interfaces.
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12. The radio interface device as claimed in claim 11, characterized in that it comprises a
plurality of digital radio modems as claimed in any one of claims 1 to 6, associated with a
single radio access technology, wherein said digital radio modems of said plurality of digital
radio modems are mutually connected by means of said first communication interfaces.
13. A gateway {500) for the interconnection of at least one wireless sensor network with at
least one wide-area communication network, wherein said gateway is characterized in that
it comprises:
at least one radio interface device as claimed in either one of claims 11 and 12, for
the exchange of data with said wireless sensors;
at least one complementary interface device (502) with said at least one wide-area
communication network, wherein said complementary interface device {502) comprises at
least one fourth communication interface, wherein said complementary interface device
(502) is connected to said at least one radio interface device by means of the cooperation
of said fourth communication interface with a first communication interface of a digital
radio modem of said radio interface device, wherein the complementary interface device
(502) comprises a protective frame of substantially equivalent dimensions to a protective
frame (201) of a digital radio modem,
wherein the fourth communication interface comprises, on an upper and lower surface of the
20 protective frame of the complementary interface device (502), at least one male SPI
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connector and at least one female SPI connector, which are designed to cooperate with the
SPI connectors of a digital radio modem or of another complementary interface device
{502), wherein the male and female SPI connectors constitute the respective terminations
of at least one data bus which is arranged internally to the frame.
14. The gateway as claimed in claim 13, characterized in that it comprises a plurality of radio
interface devices as claimed in either one of claims 11 and 12, wherein said radio interface
devices of said plurality of radio interface devices are mutually connected by means of the
cooperation of the first communication interfaces of the digital radio modems of said
plurality of radio interface devices.
The gateway as claimed in one ofclaims 13 and 14, wherein the protective frame of the
digital radio modems and the complementary devices comprises means for the attachment
of the gateway for wireless sensor networks in a cabinet or in a protective bay.