Object of the invention
The present invention relates to efficient application of Time Division Multiple
Access (TDMA) on RF Module using HT12E address lines.
Field of the invention
The present invention relates to wireless communication in general, particularly
the present invention relates to efficient usage of RF (Radio Frequency)
Modules by applying TDMA to it to increase the number of instructions which
could be sent.
Background of the Invention
The invention has 2 circuits one is transmitter the other is receiver circuit. The
remote unit uses toggle switches to receive commands, these commands are
received by a microcontroller (atmega32) [3] which processes them and sends
signals through an RF transmitter with 43 3 MHz which has HT12E encoder IC
for serial transmission.
The receiver unit has 1 to 256 receivers connected to microcontroller
(atmega32) through HT12D decoders at the receivers with different address bits
(selected by grounding them or leaving them alone as by default they are at
high.)
Brief description of accompanying drawings
Figure 1 relates to sending of data to multiple receivers through one transmitter
in accordance with an embodiment of the present invention.

Figures 2(a) and 2(b) relate to use circuits for TX and RX without technique of
present invention, without using any microcontroller to dynamically control the
address lines
Detailed description of the preferred embodiments
Figure 1 shows:-
The microcontroller gives 4 bits of parallel form of data and 8 bits of address
line data to the encoder (HT12E), it encodes them by turning this parallel data
into serial form. This serial data is given to RF Module transmitter. This radio
frequency (RF) transmission system employs Amplitude Shift Keying (ASK)
with transmitter/receiver (TX/RX) pair operating at 434 MHz The transmitter
module takes serial input and transmits these signals through RF. The
transmitted signals are received by several receiver modules placed away from
the source of transmission. The receivers pass on the serial data to the HT12D
decoders which use this serial data convert it to parallel form and compare it to
the particular address they are given, this address is used to determine if the sent
data is meant for this particular receive, if it is then the new data bits given out
by decoder else they are ignored and old values are retained.
Figures 2(a) and 2(b) shows:-
These are the usually use circuits for TX and RX without our technique, without
using any microcontroller to dynamically control the address lines.
Summary of the Invention:
According to the present invention there is provided efficient application of
Time Division Multiple Access (TDMA) on RF Module using HT12E address
lines comprises of address lines of HT12E encoder connected to an RF

transmitter, TDMA to the RF module and controlling the encoder address bits
allowing to address the respective receiver unit one at a time and allows to
connect to 256 receivers in this manner and baling to send 256 X 4(bits) = 4096
instructions instead of just 4 (an exponential increase), using 2 receivers in one
machine implementing the procedure and using 8 bits (thus 256 instructions)
characterizing that the microcontroller gives 4 bits of parallel form of data and 8
bits of address line data to the encoder (HT12E), encoding them by turning this
parallel data into serial form and this serial data is given to RF Module
transmitter, this radio frequency (RF) transmission system employing
Amplitude Shift Keying (ASK) with transmitter/receiver (TX/RX) pair
operating at 434 MHz, the transmitter module taking serial input and
transmitting these signals through R, the transmitted signals receiving several
receiver modules placed away from the source of transmission, and the
receivers passing on the serial data to the HT12D decoders using this serial data
converting it to parallel form and comparing it to the particular address they are
given, and this address is used to determine the sent data is meant for this
particular receive, and if it is then the new data bits given out by decoder else
they are ignored and old values are retained.
The address bits are changed by using the microcontroller output which has
HIGH or LOW as output to control these address lines.
The address line is grounded when microcontroller PIN connected to it is LOW
and is at 5V when microcontroller output at respective pin is HIGH thus correct
programming of the microcontroller which control the address lines and thus
control outputs of 256 receivers with decoder outputs to give 4096 bits.

The new technology is the control of address lines of HT12E encoder connected
to an RF transmitter.
2 RF transmitters of same frequency can't work simultaneously as there will be
interference between the two but we needed to send more than 4 bits (which
allow for 16 instructions) to be sent. We achieved this by applying TDMA to
the RF module and controlling the encoder address bits, this allowed us to
address the respective receiver unit one at a time and allowed us to connect to
256 receivers in this manner thus we are able to send 256 X 4(bits) = 4096
instructions instead of just 4 (an exponential increase). We used 2 receivers in
one JCB machine implementing the above procedure and using 8 bits (thus 256
instructions).
The address bits are changed by using jumpers and connecting them to ground
but we have used the microcontroller output which has HIGH or LOW as output
to control these address lines. The address line is grounded when
microcontroller PIN connected to it is LOW and is at 5V when microcontroller
output at respective pin is HIGH. Thus by the correct programming of the
microcontroller we could control the address lines and thus control outputs of
256 receivers with decoder outputs to give 4096 bits.
We also exploited the fact that receivers in RF modules tend to latch on to the
last received input and if we change the address line and go to another receiver,
it just keeps the last input in memory. This property has always been criticized
but we have used it to our advantage.

WE CLAIM:
1. Efficient application of Time Division Multiple Access (TDMA) on RF
Module using HT12E address lines comprises of address lines of HT12E
encoder connected to an RF transmitter, TDMA to the RF module and
controlling the encoder address bits allowing to address the respective receiver
unit one at a time and allows to connect to 256 receivers in this manner and
baling to send 256 X 4(bits) = 4096 instructions instead of just 4 (an exponential
increase), using 2 receivers in one machine implementing the procedure and
using 8 bits (thus 256 instructions) characterizing that the microcontroller gives
4 bits of parallel form of data and 8 bits of address line data to the encoder
(HT12E), encoding them by turning this parallel data into serial form and this
serial data is given to RF Module transmitter, this radio frequency (RF)
transmission system employing Amplitude Shift Keying (ASK) with
transmitter/receiver (TX/RX) pair operating at 434 MHz, the transmitter module
taking serial input and transmitting these signals through R, the transmitted
signals receiving several receiver modules placed away from the source of
transmission, and the receivers passing on the serial data to the HT12D decoders
using this serial data converting it to parallel form and comparing it to the
particular address they are given, and this address is used to determine the sent
data is meant for this particular receive, and if it is then the new data bits given
out by decoder else they are ignored and old values are retained.
2. Efficient Application of Time Division Multiple Access (TDMA) on RF
Module using HT12E address lines as claimed in claim 1, wherein the address
bits are changed by using the microcontroller output which has HIGH or LOW
as output to control these address lines.

3. Efficient Application of Time Division Multiple Access (TDMA) on RF
Module using HT12E address lines as claimed in claim 1 and 2, wherein the
address line is grounded when microcontroller PIN connected to it is LOW and
is at 5V when microcontroller output at respective pin is HIGH thus correct
programming of the microcontroller which control the address lines and thus
control outputs of 256 receivers with decoder outputs to give 4096 bits.