[Document Name] DESCRIPTION
[Ti t le of Invent ion] COMMUNICATION APPARATUS,
COMMUNICATION SYSTEM, CONTROL METHOD, AND STORAGE
MEDIUM ON WHICH COMMUNICATION PROGRAM HAS BEEN
STORE5 D
[Technical Field]
[0001]
The present invent ion relates to a communicat ion appa ratus, a
communicat ion system, a cont rol method and a storage medium for storing
10 a communicat ion program for properly determining a radio resource where
inter ference has occur red.
[Background Art ]
[0002]
A radio base stat ion general ly al locates a radio res ource to a radio
15 terminal and per forms wireless communicat ion wi th this radio terminal .
Radio waves are used in the wireless communicat ion, which could cause
occurrence of inter ference. The inter ference is a state that a plural i ty of
radio waves are over lapped and turned to be di fferent when those radio
waves are separately t ransmi t ted. For example, when each of two
20 different radio base stat ions uses the same radio resource in the wi reless
communicat ion, inter ference could occur at this radio resource.
[0003]
An example of a method for determining whether inter ference has
occurred at a certain radio resource in the wireless communicat ion is a
25 determinat ion method described in PTL 1.
[0004]
PTL 1 describes a method where a radio base stat ion measures an
inter ference power on a resource block basis and determines whether large
inter ference has occur red by comparing a value obtained by mul t iplying
2
the inter ference power by the t raffic volume wi th a threshold.
[Ci tat ion List ]
[Patent Li terature]
[0005]
[PTL 1] Internat ional Publ icat ion No. WO2011/055845 1
[Summary of Invent ion]
[Technical Problem]
[0006]
The method described in PTL 1, however, has a problem that i t is
10 difficul t to properly determine the occurrence of inter ference when an
inadequate threshold is set . For example, there is a problem that i t is
determined that interference has not occur red in a resource block where
inter ference has actual ly occur red when a set threshold is too large.
[0007]
15 Accordingl y, an object ive of the present invent ion is to pr ovide a
more proper determinat ion method for determining a radio resource where
inter ference has occur red.
[Solut ion to Problem]
[0008]
20 A communicat ion apparatus of the present invent ion which
uses a radio resource group compr ising a plural i ty of radio r esources,
comprises:
comparison means for mutual ly comparing interference powers of at
least two radio resources of the plural i ty of radio resources; and
25 determinat ion means for determining whether inter ference has
occurred at the radio resources compared by the comparison means based
on comparison resul ts of the comparison means.
[0009]
A communicat ion system of the present invent ion comprises:
3
a communicat ion apparatus for using a radio resource group
comprising a plural i ty of radio resources; and
another communicat ion apparatus communicable wi th the
communicat ion apparatus;
wherein the communicat ion apparatus comprises5 :
comparison means for mutual ly comparing interference powers of at least
two radio resources of the plural i ty of radio resources which ar e used for
communicat ion wi th another communicat ion apparatus; and
determinat ion means for determining whether inter ference has
10 occurred at the radio resources compared by the comparison means based
on comparison resul ts of the comparison means.
[0010]
A cont rol method of the present invent ion for control l ing a
communicat ion apparatus for using a radio resource group comprising a
15 plural i ty of radio resources, compris es:
mutual ly comparing inter ference powers of at least two radio
resources of the plural i ty of radio resources; and
determining whether inter ference has occur red at the compared
radio resources based on a resul t of the comparison.
20 [0011]
A storage medium for stor ing a communicat ion program of
the present invent ion for al lowing a computer to con t rol a communicat ion
apparatus for using a radio resource group comprising a plural i ty of radio
resources,
25 the communicat ion program for having the computer execute the
processes of:
mutual ly comparing inter ference powers of at least two radio
resources of the plural i ty of radio resources; and
determining whether inter ference has occur red at the compared
4
radio resources based on resul ts of the process.
[Advantageous Effects of Invent ion]
[0012]
Wi th the present invent ion, a radio resource where inter ferenc e has
occurred can be more properly determined5 .
[Brief Descript ion of Drawings ]
[0013]
[Fig.1] Fig. 1 is a block diagram of a communicat ion apparatus related to
the fi rst exemplary embodiment .
10 [Fig.2] Fig. 2 is a block diagram of a communicat ion apparatus related to
the second exemplary embodiment .
[Fig.3] Fig. 3 is a block diagram of a communicat ion apparatus related to
the thi rd exemplary embodiment .
[Fig.4] Fig. 4 is a block diagram of a communicat ion apparatus related to
15 the fi rst to thi rd exemplary embodiments.
[Fig.5] Fig. 5 is a block diagram of a communicat ion apparatus related to
the fi rst to thi rd exemplary embodiments.
[Fig.6] Fig. 6 is a diagram showing an example of dividing al l bands that a
communicat ion apparatus uses into k + 1 resource block s.
20 [Fig.7] Fig. 7 is a diagram showing an example of an occurrence si tuat ion
of inter ference powers across the resource blocks of Fig. 6.
[Fig.8] Fig. 8 is a table showing an example of informat ion on inter ference
powers of respect ive resource blocks.
[Fig.9] Fig. 9 is a table showing an example of determinat ion resul ts saved
25 in a memory 50.
[Fig.10] Fig. 10 is a diagram showing an example of al locat ion of resource
blocks.
[Fig.11] Fig. 11 is a diagram showing an example of comparison resul ts.
[Fig.12] Fig. 12 is a diagram showing an example of comparison resul ts.
5
[Fig.13] Fig. 13 is a flowchart showing a speci fic example of a
determinat ion method of a determinat ion uni t .
[Fig.14] Fig. 14 is a block diagram showing a configurat ion example of a
communicat ion system of the fi rst to third exemplary embodiments.
[Fig.15] Fig. 15 is a block diagram showing a configurat ion example of 5 a
communicat ion system of the fi rst to third exemplary embodiments.
[Descript ion of Embodiments ]
[0014]
(First Exemplary Embodiment )
10 Fig. 1 shows a configurat ion of a communicat ion apparatus in the
first exemplary embodiment .
[0015]
The communicat ion apparatus 100 uses a plural i ty of radio
resources. In this descript ion, a group of radio resources which include a
15 plural i ty of radio resources used by the communicat ion apparatus 100 is
refer red to as a radio resource group. Here, these radio resources may be
ones that have at least a predetermined f requency bandwidth. For
example, the radio resources may be a resource block that is divided into
t ime and frequency domains. The radio resources may be also a resource
20 block having a three-dimensional st ructure which is made of t ime,
frequencies and space domains ( for example, antenna select ion). Further,
a resource block having this three-dimensional st ructure is real ized by
Mul t iple- Input and Mul t iple-Output (MIMO) . Further, the resource block
may be also radio resources having a three -dimensional structure which i s
25 made of t ime, frequencies and codes. The radio resources having this
three-dimensional structure are real ized, for example, by W-CDMA
(Wideband Code Division Mul t iple Access).
[0016]
The communicat ion apparatus 100 has at least a comparison uni t 10
6
and a determinat ion uni t 20. The comparison uni t 10 compares mutual
inter ference powers of at least two radio resources of a plural i ty of radio
resources and outputs comparison resul ts which are resul ts of the
comparison. The determinat ion uni t 20 inputs the comparison resul ts and
determines whether inter ference has occurred at the radio resource5 s
compared by the comparison uni t 10 based on the comparison resul ts.
[0017]
Next , behaviors of the communicat ion apparatus 100 in this
exemplary embodiment are explained.
10 [0018]
Fi rst l y, the compar ison uni t 10 compares mutual interference
powers of at least two radio resources of a plural i ty of radio resources and
outputs compar ison resul ts which are resul ts of the comparison. Here, as
long as these comparison resul ts represent the resul ts of the comparison,
15 detai ls of thei r contents are not important .
[0019]
Next , the determinat ion uni t 20 determines whether interference has
occurred at the radio resources compared by the comparison uni t 10 based
on the compar ison resul ts.
20 [0020]
As ment ioned above, the communicat ion apparatus 100 in this
exemplary embodiment determines whether interference has occur red at
the radio resources included in the radio resource group based on the
comparison resul ts which are resul ts of comparing the interference powers
25 of at least two radio resources. Therefore , wi th the communicat ion
apparatus 100 in this exemplary embodiment , a radio resource where
inter ference has occur red can be properly determined.
[0021]
(Second Exemplary Embodiment )
7
Fig. 2 shows a configurat ion of a communicat ion apparatus in the
second exemplary embodiment .
[0022]
The communicat ion apparatus 200 uses a plural i ty of radio
resources. A group of radio resources which include a plural i ty of radi5 o
resources used by the communicat ion apparatus 200 is referred to as a
radio resource group.
[0023]
The communicat ion apparatus 200 has at least a compar ison uni t 10,
10 a determinat ion uni t 20 and an al locat ion uni t 30. The comparison uni t
10 and the determinat ion uni t 20 are as stated in the fi rst exemplary
embodiment . The determinat ion uni t 20 in thi s exemplary embodiment
outputs informat ion showing whether interference has occur red at the radio
resources compared by the compar ison uni t 10 as determinat ion resul ts.
15 The al locat ion uni t 30 inputs the determinat ion resul ts and al locates radio
resources to another communicat ion apparatus based on the determinat ion
resul ts.
[0024]
Next , behaviors of the communicat ion apparatus 200 in this
20 exemplary embodiment are explained.
[0025]
Behaviors of the comparison uni t 10 and the determinat ion uni t 20
are as stated in the fi rst exemplary embodiment .
[0026]
25 The determinat ion uni t 20 in this exemplary embodiment outputs
informat ion showing whether inter ference has occur red at the radio
resources compared by the compar ison uni t 10 as determinat ion resul ts.
The determinat ion resul ts which are output f rom the determinat ion uni t
may be only the informat ion to ident i fy a radio resource where interference
8
has occur red, only the informat ion to ident ify a radio resource where
inter ference has not occur red or the informat ion to ident ify whether
inter ference has occur red per radio resource.
[0027]
Next , the al locat ion uni t 30 al locates the radio resources wher5 e
inter ference has not occurred to another communicat ion apparatus based on
the determinat ion resul ts.
[0028]
The inter ference powers may be computed by the communicat ion
10 apparatus 200 or not ified by another communicat ion apparatus which
differs from the communicat ion apparatus 200.
[0029]
As ment ioned above, the communicat ion apparatus 200 in this
exemplary embodiment al locates radio resources to another communicat ion
15 apparatus based on the determinat ion resul ts of whether inter ference has
occurred at the radio resources included in a radio resource group.
Therefore, the communicat ion apparatus 200 in this exemplary embo diment
can al locate the radio resources where inter ference has not occurred to
another communicat ion apparatus.
20 [0030]
(Third Exemplary Embodiment)
Fig. 3 shows a communicat ion apparatus in the thi rd exemplary
embodiment .
[0031]
25 The communicat ion apparatus 300 uses a plural i ty of radio
resources. A group of radio resources which include a plural i ty of radio
resources used by the communicat ion apparatus 300 is referred to as a
radio resource group.
[0032]
9
The communicat ion apparatus 300 has at least a compa r ison uni t 10,
a determinat ion uni t 20, a comput ing uni t 25 and an al locat ion uni t 35.
The comparison uni t 10 and the determinat ion uni t 20 are as stated in the
first exemplary embodiment . The determinat ion uni t 20 in this exemplary
embodiment outputs informat ion showing whether interference ha5 s
occurred at the radio resources compared by the comparison uni t 10 and
one showing values of the inter ference which has occur red at the compared
radio resources as determinat ion resul ts. The comput ing uni t 25
computes a mean value of inter ference powers of a plural i ty of radio
10 resources included in the radio resource group based on the determinat ion
resul ts input by the determinat ion uni t 20.
[0033]
Next , behaviors of the communicat ion apparatus 300 in this
exemplary embodiment are explained.
15 [0034]
Behaviors of the comparison uni t 10 and the determinat ion uni t 20
are as stated in the fi rst exemplary embodiment .
[0035]
After the determinat ion, the determinat ion uni t 20 in this exemplary
20 embodiment outputs informat ion showing whether interference has
occurred at the radio resources compared by the comparison uni t 10 and
one showing the st rength of the inter ference powers occurring at the
compared radio resources as determinat ion resul ts.
[0036]
25 Next , the comput ing uni t 25 computes a mean value of inter ference
powers of a plural i ty of radio resources included in the radio resource
group based on the determinat ion resul ts. At the t ime, the comput ing uni t
25 excludes inter ference powers of the radio resources where i t i s
determined that inter ference has occur red to compute a mean value.
10
[0037]
The al locat ion uni t 35 al locates radio resources to another
communicat ion apparatus based on the comput ing resul ts output f rom the
comput ing uni t 25. At the t ime, the al locat ion u ni t 35 does not al locate
the radio resources which are determined to be under inter ference t5 o
another communicat ion apparatus.
[0038]
Here, the communicat ion apparatus in the thi rd exemplary
embodiment of the present exemplary embodiments is now explained more
10 speci fical ly wi th reference to Fig. 4.
[0039]
A configurat ion in Fig. 4 is nothing more than one aspect of the
present exemplary embodiments. The present exemplary embodiments
can be per formed through various means. For example, the present
15 exemplary embodiments can be per formed wi th hardware, sof tware or any
combinat ion thereof. Besides, the present exemplary embodiments may
be also appl ied to other exemplary embodiments.
[0040]
The communicat ion apparatus 300 has a memory 50 and a processor
20 60.
[0041]
Fig. 5 is an example of speci fical ly showing a configurat ion of the
processor 60 in Fig. 4. As shown in Fig. 5, the processor 60 has funct ions
of the comparison uni t 10, the determinat ion uni t 20 and the comput ing
25 uni t 25 shown in the foregoing exemp lary embodiments and ones of a
scheduler 37 and a transmi t t ing/ receiving uni t 40. It is noted that the
memory 50 is conf igured separately f rom the processor 60 in the example
shown in Fig. 5, but the memory 50 may be included in the processor 60.
In this case, the memory 50 is included in at least one of the comparison
11
uni t 10, the determinat ion uni t 20 and the comput ing uni t 25. For the
explanat ion below, Fig. 5 is referenced.
[0042]
Hereinaf ter, for the purpose of i l lustrat ion, a resource block (RB)
which is one of radio resources is used for the explanat ion in place of 5 a
"radio resource", which does not mean that the present embodiment is
appl ied only to resource block.
[0043]
Also, for i l lust rat ive purposes, a radio resource is replaced wi th a
10 resource block and then a radio resource group is replaced wi th al l bands
that the communicat ion apparatus 300 uses.
[0044]
Fig. 6 shows an example where al l bands used by the
communicat ion apparatus 300 are divided into k + 1 resource blocks from
15 RB0 to RBk .
[0045]
Fig. 7 shows an example of an occur rence si tuat ion of interference
powers in each resource block shown in Fig. 6. In the fol lowing
descript ion, i t is explained that large interference has occur red only at RBn
20 in al l bands that the communicat ion appara tus 300 uses.
[0046]
The t ransmi t t ing/ receiving uni t 40 computes inter ference powers of
respect ive resource blocks, using received signals. It is noted that
inter ference powers computed by the other end of communicat ion may be
25 used as ones of resource blocks. In this case, the t ransmi t t ing/receiving
uni t 40 receives informat ion on inter ference powers of respect ive resource
blocks.
[0047]
It is noted that these received signals are, for example, pi lot signals.
12
The pi lot signals are signals which are t ransmi t ted in a certain def ined bi t
(chip in CDMA) pat tern. Because the pi lot signals are ones wi th a certain
predetermined pat tern, the aforement ioned communicat ion apparatus 300
which receives these signals can measure their received or interference
powers. As an example of the pi lot signals, reference signals are used i5 n
Long Term Evolut ion (LTE). The reference signals are defined according
to thei r reference signal sequences in the frequency domain. For example,
Zadoff -Chu (ZC) sequences, which are one of CAZAC sequences, are used
because i t is desi rable that the reference signal sequences are uni form in
10 the f requency characterist ics and they have good autocor relat ion and
cross-correlat ion characterist ics.
[0048]
Fig. 8 shows an example of informat ion on inter ference powers of
respect ive resource blocks. It is noted that a form of informat ion is not
15 l imi ted to the one in Fig. 8.
[0049]
The comparison uni t 10 compares the mutual interference powers of
at least two resource blocks of k + 1 resource blocks from RB0 to RBk .
[0050]
20 This comparison of the compar ison uni t 10 is based on a di fference
in inter ference powers of two resource blocks. For example, the
comparison uni t 10 obtains a di fference between inter ference powers of
RBn -1 and RBn , and outputs a comparison resul t that the di fference between
the inter ference powers of RBn -1 and RBn is X (dBm).
25 [0051]
The comparison resul ts are saved in the memory 50.
[0052]
Next , the determinat ion uni t 20 reads the comparison resul ts from
the memory 50 and star ts determinat ion. For example, the determinat ion
13
uni t 20 reads the comparison resul t that the difference between the
inter ference powers of RBn -1 and RBn is X (dBm), and outputs the
informat ion that interference has occurred at RBn and the one showing a
value of the interference power of RBn as the determinat ion resul ts when
the compar ison resul t is over a predetermined value5 .
[0053]
Also, at the determinat ion uni t 20, the predetermined value may be
prel iminari ly set or vary according to ci rcumstances. Here, these
circumstances mean, for example, the communicat ion envi ronments, which
10 refer to recept ion qual i t ies or throughputs, such as CQI (Channel Qual i ty
Indicator ), RSRP (Reference Signal Received Power ), RSRQ (Reference
Signal Received Qual i ty) , and path loss.
[0054]
The determinat ion resul ts are saved in the memory 50.
15 [0055]
Fig. 9 shows an example of the determinat ion resul ts saved in the
memory 50. The determinat ion resul ts may include inter ference power
values of respect ive resource blocks, informat ion showing the st rength of
inter ference which has occur red at each resource block and informat ion
20 about others including inter ference powers and determinat ion methods.
It may be also shown in one bi t of informat ion whether interference has
occurred. For example, the configurat ion may be such that , if the bi t is
"0", i t is shown that inter ference has occur red at a corresponding resource
block, and if the bi t is "1", i t is shown that interference has not occur red at
25 a corresponding resource block.
[0056]
Next , the comput ing uni t 25 reads the determinat ion resul ts from
the memory 50 and starts comput ing a mean value of inter ference powers
of a plural i ty of resource blocks. At the t ime, the comput ing uni t 25
14
excludes interference powers of the resource blocks which the
determinat ion uni t 20 determined to be under inter ference .
[0057]
In this computat ion, the comput ing uni t 25 may also exclude the
inter ference powers of respect ive resource blocks next to the one which i5 s
determined to be under inter ference based on the determinat ion resul ts
from the mean value computat ion. For example, if interference has
occurred at RBn , the inter ference powers of RBn -1 and RBn+1 may be also
excluded from the mean value computat ion.
10 [0058]
In addi t ion, at the comput ing uni t 25, the number of excluded
resource blocks from the mean value calculat ion may be prel iminari ly set
or changed according to ci rcumstances. Here, these ci rcumstances mean,
for example, the communicat ion envi ronments, which refer to recept ion
15 qual i t ies or throughputs, such as CQI (Channel Qual i ty Indicator ).
[0059]
The comput ing uni t 25 may compute est imate values of SIR
(Signal -to- Inter ference Rat io) per resource block using the interference
power values.
20 [0060]
In the SIR est imate value computat ion, the SIR es t imate values may
be cor rected according to inter ference power st rength of resource blocks.
For example, if the interference power st rength of a resource block is over
a predetermined value, the computed SIR est imate value may be corrected
25 wi th a value according to the strength of the inter ference power which has
occurred at the resource block (such as a value proport ional to the
inter ference power strength). Also, for example, for a resource block
which is determined to be under inter ference based on the determinat ion
resul ts, i ts computed SIR est imate value may be corrected wi th a value
15
according to the strength of the inter ference power which has occur red at
the resource block (such as a value proport ional to the inter ference power
strength).
[0061]
The comput ing uni t 25 outputs a mean value of inter ference power5 s
and SIR est imate values, both of which are the comput ing resul ts.
[0062]
The comput ing resul ts are saved in the memory 50.
[0063]
10 The scheduler 37 reads the comput ing resul ts from the memory 50
and al locates a resource block to another communicat ion apparatus.
[0064]
Fig. 10 shows an example of al locat ion of resource blocks. The
scheduler 37 may al locate di fferent communicat ion apparatuses
15 respect ively or same communicat ion apparatus for each s ide of resource
blocks, which is determined to be under interference .
[0065]
The scheduler 37 may refer to interference powers of respect ive
resource blocks when i t al locates a resource block to another
20 communicat ion apparatus.
[0066]
The present exemplary embodiments are specif ical ly explained
above based on the preferred exemplary embodiments, but i t goes wi thout
saying that the present exemplary embodiments are not l imi ted to the above
25 and various changes or addi t ion may be made wi thout depart ing f rom i t s
substance. The detai ls are described below.
[0067]
(Comparison Method)
For example, in the fi rst to thi rd exemplary embodiments, the
16
comparison uni t 10 compares the interference powers of at least two radio
resources of a plural i ty of radio resources. Here, a specific example of
the compar ison at the comparison uni t is now explained.
[0068]
It is noted that an example of the comparison method of th5 e
comparison uni t 10 is a method for comparing an inter ference power of the
radio resource which is a target for comparison wi th the inter ference
power/powers of one or a plural i ty of radio resource/ resources which is/are
the other side of the comparison target / targets. In this case, the
10 comparison uni t 10 changes targets of comparison to compare when i t
finishes compar ing radio resources which are targets of comparison. For
example, after the comparison uni t 10 compares the target of comparison
wi th the other target , i t may interchange the radio resources f rom the target
to the other target of comparison and from the other target to the target of
15 comparison. The determinat ion uni t 20 in this case determines whether
inter ference has occur red at the targets of comparison.
[0069]
For example, the comparison at the comparison uni t 10 may be
based on obtaining a di fference between a minimum value of inter ference
20 powers in a radio resource group and an interference power of a compared
radio resource.
[0070]
This comparison method is speci fical ly explained in Fig. 8.
[0071]
25 In Fig. 8, an interference power value of RB1 is the minimum value
of inter ference powers in al l bands. In this case, di fferences between an
inter ference power value of RB1 and ones of other RBs are obtained
respect ivel y. Fig. 11 shows resul ts of the obtained di fferences.
[0072]
17
In this case, the resul ts whether the obtained di fferences are over a
predetermined value may act as a benchmark of the determinat ion method.
[0073]
Besides, the compar ison at the comparison uni t 10 may be also
based on obtaining a rat io of mutual interference powers of compared radi5 o
resources.
[0074]
This comparison method is speci fical ly explained in Fig. 8.
[0075]
10 For example, in Fig. 8, rat ios of an inter ference power value of RB0
to ones of other RBs are obtained respect ivel y. Fig. 12 shows resul ts of
the obtained rat ios.
[0076]
In this case, whether the resul ts of the obtained rat ios are over a
15 predetermined value may act as a benchmark of the determinat ion method.
(Determinat ion Method)
Besides, in the fi rst to thi rd exemplary embodiments, the
determinat ion uni t 20 determines, based on the comparison resul ts,
whether interference has occur red at radio resources included in the radio
20 resource group which is compared at the comparison uni t 10. A specific
example of the determinat ion method at the determinat ion uni t 20 is now
explained wi th reference to Fig. 13.
[0077]
Here, this explains an example where the comparison at the
25 comparison uni t 10 is based on obtaining a di fference of mutual
inter ference powers of compared radio resources.
[0078]
Fi rst l y, i t is determined whether al l the comparison resul ts sat isfy
the fi rst condi t ion (S1). Here, this fi rst condi t ion is one that a di fference
18
of the inter ference powers is the fi rst predetermined value or less. The
first predetermined value may be a fixed or variat ion value . In the case
of a var iat ion value, for example, i t may be a value which changes
according to communicat ion environments.
[5 0079]
If al l the comparison resul ts sat isfy the fi rst condi t ion (S1: YES), i t
is selected whether the comparison resul ts are determi ned wi th the second
condi t ion (S2) . If the comparison resul ts are not determined wi th the
second condi t ion (S2: NO) , the determinat ion ends and i t is determined
10 that inter ference has not occur red at the radio resources which sat isfy the
first condi t ion.
[0080]
Here, this second condi t ion is one that the minimum value of
inter ference powers shown by the radio resources included in the radio
15 resource group is the second predetermined value or more. The second
predetermined value may be a fixed or variat ion value. In the case of a
variat ion value, for example, i t may be a value which changes according to
communicat ion envi ronments.
[0081]
20 If the comparison resul ts sat isfy the first condi t ion (S1: YES), the
comparison resul ts are determined wi th the second co ndi t ion (S2: YES)
and the comparison resul ts sat isfy the second condi t ion (S3: YES) , i t is
determined that inter ference has occur red at a radio resource which
sat isfies the first condi t ion.
25 [0082]
If the comparison resul ts sat isfy the first condi t ion (S1: YES), the
comparison resul ts are determined wi th the second condi t ion (S2: YES)
and the comparison resul ts do not sat isfy the second condi t ion (S3: NO), i t
is determined that inter ference has not occurred at a radio resource which
19
sat isfies the first condi t ion.
[0083]
If at least one of al l the comparison resul ts does not sat isfy the fi rst
condi t ion (S1: NO) , the proport ion of the radio resources which sat isfy the
first condi t ion in the radio resource group is computed. Then i t i5 s
determined whether the proport ion of the radio resources which sat isfy the
first condi t ion in the radio resource group sat isfies the thi rd condi t ion.
[0084]
Here, this thi rd condi t ion is one that the proport ion of the radio
10 resources which sat isfy the fi rst condi t ion in the radio resource group is
the second predetermined value or less.
[0085]
If the proport ion of the radio resources which sat isfy the fi rst
condi t ion in the radio resource group does not sat isfy the thi rd condi t ion
15 (S4: NO), the determinat ion ends and i t is determin ed that interference has
occurred at a radio resource which does not sat isfy the fi rst condi t ion.
[0086]
If the proport ion of the radio resources which sat isfy the fi rst
condi t ion in the radio resource group sat isfies the thi rd condi t ion (S4:
20 YES), a larger value than the first predetermined value used in the first
condi t ion is set as the thi rd predetermined value and the fourth condi t ion
t h at "t h e comp a r i s o n r es u l t s ar e t h e t h i r d p r ed et e rmi n ed v a l u e o r mo r e ” i s
set .
[0087]
25 Then if the comparison resul ts do not sat isfy the fourth condi t ion
(S5: NO), the determinat ion ends and i t is determined that interference has
occurred at a radio resource which does not sat isfy the fourth condi t ion.
[0088]
By contrast , if the comparison resul ts sat isfy the fourth condi t i on
20
(S5: YES) , the determinat ion ends and i t is determined that interference
has not occurred at radio resources which sat isfy the fourth condi t ion.
[0089]
(Speci fic Examples of Communicat ion Apparatus and Another
Communicat ion Apparatus5 )
For example, the communicat ion apparatus in the fi rst to thi rd
exemplary embodiments may be a base stat ion. In this case, another
communicat ion apparatus is a target to which the base stat ion al locates
radio resources, such as a mobi le stat ion, a femtocel l base stat ion and a
10 microcel l base stat ion.
[0090]
Fig. 14 shows a conf igurat ion example of a communicat ion system
of the fi rst to thi rd exemplary embodiments. In the configurat ion
example in Fig. 14, a communicat ion system where a communicat ion
15 apparatus 400 and another communicat ion apparatus 500 communicate over
radio is configured. The communicat ion apparatus 400 is configured wi th
the comparison uni t 10, the determinat ion uni t 20, the al locat ion uni t 30
and a t ransmi t t ing/receiving uni t 40. Another communicat ion app aratus
500 is configured wi th a t ransmi t t ing/ receiving uni t 70. The
20 transmi t t ing/ receiving uni t 40 of the communicat ion apparatus 400 and the
transmi t t ing/ receiving uni t 70 of another communicat ion apparatus 500
receive or transmi t informat ion from or to each other.
[0091]
The comparison uni t 10 of the communicat ion apparatus 400
25 mutual ly compares interference powers of at least two radio resources of a
plural i ty of radio resources and outputs comparison resul ts which are
resul ts of the comparison. The de terminat ion uni t 20 inputs the
comparison resul ts, determines whether inter ference has occur red at the
radio resources compared by the comparison uni t 10 based on the
21
comparison resul ts and outputs informat ion showing whether inter ference
has occur red at the radio resources compared by the comparison uni t 10 as
determinat ion resul ts. The al locat ion uni t 30 inputs the determinat ion
resul ts and al locates radio resources to another communicat ion apparatus
500 based on the determinat ion resul ts. The t ransmi t t ing/receiving uni 5 t
40 of the communicat ion apparatus 400 communicates wi th another
communicat ion apparatus 500 using the radio resources al located to
another communicat ion apparatus 500 by the al locat ion uni t 30.
[0092]
10 Fig. 15 shows another configurat ion example of a communicat ion
system of the f irst to thi rd exemplary embodiments. In the configurat ion
example in Fig. 15, wi reless communicat ion between a communicat ion
apparatus 600 and another communicat ion apparatus 700 configures the
communicat ion system. The communicat ion apparatus 600 is configured
15 wi th an al locat ion uni t 31 and a t ransmi t t ing/ receiving uni t 41. Another
communicat ion apparatus 700 is configured wi th a comparison uni t 11, a
determinat ion uni t 21 and a t ransmi t t ing/ receiving uni t 71. The
transmi t t ing/ receiving uni t 41 of the communicat ion apparatus 600 and the
transmi t t ing/ receiving uni t 71 of another communicat ion apparatus 700
20 receive or transmi t informat ion from or to each other.
[0093]
The comparison uni t 11 of another communicat io n apparatus 700
mutual ly compares interference powers of at least two radio resources of a
plural i ty of radio resources and outputs comparison resul ts which are
25 resul ts of the comparison. The determinat ion uni t 21 inputs the
comparison resul ts, determines whether inter ference has occur red at the
radio resources compared by the comparison uni t 11 based on the
comparison resul ts and outputs informat ion showing whether inter ference
has occurred at the radio resources compared by the comparison uni t 11 as
22
determinat ion resul ts to the t ransmi t t ing/ receiving uni t 71. The
transmi t t ing/ receiving uni t 71 of another communicat ion apparatus 700
transmi ts the determinat ion resul ts to the transmi t t ing/ receiving uni t 41 of
the communicat ion apparatus 600. The transmi t t ing/ receiving uni t 41 of
the communicat ion apparatus 600 inputs the received determinat ion resul 5 ts
on the al locat ion uni t 31 and al locates radio resources to another
communicat ion apparatus 700 based on the determinat ion resul ts. The
transmi t t ing/ receiving uni t 41 of the communicat ion apparatus 600
communicates wi th another communicat ion apparatus 700 using the radio
10 resources al located to another communicat ion apparatus 700 by the
al locat ion uni t 31.
[0094]
Also, each process of the foregoing exemplary embodiments may be
executed by software. This means a computer program for per forming
15 each process may be read and executed by CPU (Central Processing Uni t)
included in a communicat ion apparatus. If each process is per formed by
a program, the same processing detai ls as the processes in the
aforement ioned exemplary embodiments can be done. In addi t ion, the
above program may be stored in a non -transi tory medium, including a
20 semiconductor storage, such as ROM (Read Only Memory) , RAM (Random
Access Memory) and a flash memor y, an opt ical disk, a magnet ic disk and a
magnet ic opt ical disk.
[0095]
Whi le the invent ion has been part icularly shown and described wi th
25 reference to exemplary embodiments thereof, the invent ion is not l imi ted
to these embodiments. It wi l l be understood by those of ordinary ski l l in
the art that various changes in form and detai ls may be made therein
wi thout depar t ing from the spi ri t and scope of the present invent ion as
defined by the claims.
23
[0096]
This appl icat ion is based upon and claims the benefi t of pr iori ty
from Japanese patent appl icat ion No. 2013-200683, fi led on September 27,
2013, the disclosure of which is incorporated herein in i ts ent i rety by
reference5 .
[0097]
The whole or part of the exemplary embodiments disclosed above
can be described as, but not l imi ted to, the fol lowing supplementary notes .
[0098]
10 (Supplementary note 1)
A communicat ion apparatus which uses a radio resource group
comprising a plural i ty of radio resources, the communicat ion apparatus
comprising:
comparison means for mutual ly comparing interference powers of at
15 least two radio resources of the plural i ty of radio resources; and
determinat ion means for determining whether inter ference has
occurred at the radio resources compared by the comparison means based
on comparison resul ts of the comparison means.
[0099]
20 (Supplementary note 2)
The communicat ion apparatus of supplementary note 1, wherein the
determinat ion means outputs informat ion showing whether interference has
occurred at the compared radio resources a s determinat ion resul ts of the
determinat ion.
25 [0100]
(Supplementary note 3)
The communicat ion apparatus of supplementary note 2, comprising
al locat ion means for al locat ing a radio resource to another communicat ion
apparatus communicable wi th the communica t ion apparatus based on the
24
determinat ion resul ts.
[0101]
(Supplementary note 4)
The communicat ion apparatus of supplementary note 2, comprising
comput ing means for comput ing a mean value of interference powers of th5 e
plural i ty of radio resources included in the radio resource group based on
the determinat ion resul ts.
[0102]
(Supplementary note 5)
10 The communicat ion apparatus of any one of supplementary notes 2
to 4, wherein the determinat ion resul ts comprise informat ion for
ident ifying a radio resource where inter ference has occurred.
[0103]
(Supplementary note 6)
15 The communicat ion apparatus of any one of supplementary notes 2
to 4, wherein the determinat ion resul ts compr ise informat ion according to
strength of occur ring inter ference.
[0104]
(Supplementary note 7)
20 The communicat ion apparatus of any one of supplementa ry notes 1
to 6, wherein the comparison made by the comparison means is based on
differences of the mutual interference powers of the plural i ty of radio
resources.
[0105]
25 (Supplementary note 8)
The communicat ion apparatus of any one of supplementa ry notes 1
to 6, wherein the comparison made by the comparison means is based on
differences between a minimum inter ference power detected in the radio
resource group and the inter ference powers of th e plural i ty of radio
25
resources.
[0106]
(Supplementary note 9)
The communicat ion apparatus of any one of supplementa ry notes 1
to 6, wherein the comparison made by the comparison means is based on 5 a
rat io of the mutual interference powers of the plural i ty o f radio resources.
[0107]
(Supplementary note 10)
The communicat ion apparatus of any one of supplementa ry notes 1
10 to 9, wherein the determinat ion of the determinat ion means is one whether
the compar ison resul ts sat isfy a fi rst condi t ion.
[0108]
(Supplementary note 11)
The communicat ion apparatus of supplementa ry notes 10, wherein
15 the determinat ion of the determinat ion means is one whether the
comparison resul ts sat isfy a second condi t ion i f the comparison resul ts do
not sat isfy the fi rst condi t ion.
[0109]
(Supplementary note 12)
20 The communicat ion apparatus of supplementary note 10 or 11,
wherein the determinat ion means calculates a radio resource count which is
the number of radio resources determined to sat isfy the fi rst condi t ion in
comparison resul ts and determines whether the comparison resul ts sat isfy a
fourth condi t ion if a proport ion of the radio resource count to the number
25 of the radio resources included in the radio resource group sat isfies a thi rd
condi t ion.
[0110]
(Supplementary note 13)
The communicat ion apparatus of any one of supplementa ry notes 10
26
to 12, wherein the fi rst condi t ion is that the di fference of the inter ference
powers of the radio resources compared by the comparison means is a first
predetermined value or more.
[0111]
(Supplementary note 145 )
The communicat ion apparatus of any one of supplementa ry notes 10
to 12, wherein the first condi t ion is that the rat io of the inter ference
powers of the radio resource compared by the comparison means is a f irst
predetermined value or more.
10 [0112]
(Supplementary note 15)
The communicat ion apparatus of supplementa ry note 11, wherein
the second condi t ion is that the minimum inter ference power detected in
the radio resource group is a second predetermined value or more.
15 [0113]
(Supplementary note 16)
The communicat ion apparatus of supplementa ry note 12, wherein
the thi rd condi t ion is that the proport ion is a predetermined value or more.
[0114]
20 (Supplementary note 17)
The communicat ion apparatus of supplementa ry note 12, wherein
the fourth condi t ion i s that the di fference or the rat io of the interference
powers of the radio resources compared by the compar ison means is a third
predetermined value or more and the thi rd predetermined value is larger
25 than the fi rst predetermined value.
[Reference Signs List]
[0115]
100, 200, 300, 400, 500, 600, 700 Communicat ion apparatus
10, 11 Comparison uni t
27
20, 21 Determinat ion uni t
25 Comput ing uni t
30, 35 Al locat ion uni t
37 Scheduler
40, 41, 70, 71 Transmi t t ing/ receiving uni 5 t
50 Memory
60 Processor
28
[Document Name] CLAIMS
[Claim 1]
A communicat ion apparatus which uses a radio resource group
comprising a plural i ty of radio resources, the communicat ion apparatus
comprising5 :
comparison means for mutual ly comparing interference powers of at
least two radio resources of the plural i ty of radio resources; and
determinat ion means for determining whether inter ference has
occurred at the radio resources compared by the comparison means based
10 on comparison resul ts of the comparison means.
[Claim 2]
The communicat ion apparatus of claim 1, wherein the determinat ion
means outputs informat ion showing whether inter ference has occur red at
the compared radio resources as determinat ion resul ts of the determinat ion.
15 [Claim 3]
The communicat ion apparatus of claim 2, comprising al locat ion
means for al locat ing a radio resource to another communicat ion apparatus
communicable wi th the communicat ion apparatus based on the
determinat ion resul ts.
20 [Claim 4]
The communicat ion apparatus of claim 2, comprising comput ing
means for comput ing a mean value of inter ference powers of the plural i ty
of radio resources included in the radio resource group based on the
determinat ion resul ts.
25 [Claim 5]
The communicat ion apparatus of any one of claims 2 to 4, wherein
the determinat ion resul ts comprise informat ion f or ident i fying a radio
resource where inter ference has occur red.
[Claim 6]
29
The communicat ion apparatus of any one of claims 2 to 4, wherein
the determinat ion resul ts comprise informat ion according to strength of
occurr ing inter ference.
[Claim 7]
The communicat ion apparatus of any one of claims 1 to 6, wherei5 n
the comparison made by the comparison means is based on differences of
the mutual interference powers of the plural i ty of radio resources.
[Claim 8]
A communicat ion system comprising:
10 a communicat ion apparatus for using a radio resource group
comprising a plural i ty of radio resources; and
another communicat ion apparatus communicable wi th the
communicat ion apparatus;
wherein the communicat ion apparatus comprises:
15 comparison means for mutual ly comparing i nterference powers of at
least two radio resources of the plural i ty of radio resources which are used
for communicat ion wi th another communicat ion apparatus; and
determinat ion means for determining whether inter ference has
occurred at the radio resources compared by the comparison means based
20 on comparison resul ts of the comparison means.
[Claim 9]
A cont rol method for cont rol l ing a communicat ion apparatus for
using a radio resource group comprising a plural i ty of radio resources,
comprising:
25 mutual ly comparing inter ference powers of at least two radio
resources of the plural i ty of radio resources; and
determining whether inter ference has occur red at the compared
radio resources based on a resul t of the comparison.
[Claim 10]
30
A storage medium for storing a communicat ion program for
al lowing a computer to cont rol a communicat ion apparatus for using a
radio resource group compr ising a plural i ty of radio resources,
the communicat ion program for having the computer execute the
processes of5 :
mutual ly comparing inter ference powers of at least two radio
resources of the plural i ty of radio resources; and
determining whether inter ference has occur red at the compared
radio resources based on resul ts of the process.