JPH08162998A - Spread spectrum pulse position modulation communication system - Google Patents

Abstract

(57) [Summary] [Objective] To provide a spread spectrum pulse position modulation method that is effective even under multipath fading. [Structure] In a transmitter, data is divided into log ₂ M bits and input to a differential encoding pulse position generator (DPPM) 4. The DPPM 4 differentially encodes continuous log ₂ M-bit data, and generates a pulse at a corresponding frame position based on the obtained data. The pulse is used as a trigger to output the spread code of the L chip from the PN signal generator 6. This signal is multiplied by the carrier wave fc and transmitted.
The received signal is input to the same PN matched filter 13 as the spreading code used on the transmitting side. When the input spread code pattern and the pattern of the PN matched filter 13 match, a pulse for one chip section is output. Since the position of the pulse is output to the slot corresponding to the transmission information in the frame M slot, the position of the pulse of the output is determined and the corresponding data is used as the reception data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spread spectrum pulse position modulation communication system, and more particularly to a spread spectrum communication system and a direct spread system pulse position modulation communication system. For example, it is applied to a radio communication (RF) modem.

[0002]

2. Description of the Related Art A SAW (surface acoustic wave) matched filter is usually constructed by a delay of the same number of stages as the spreading code length used. Therefore, when this is used for demodulation, one spread code (sequence) on / off keying system or a code shift keying system in which any one of a plurality of spread codes is selected by information is adopted. . At this time, the modulation of information is limited to the spread code length (cycle) or an integer multiple thereof in the former case. In other words, the information transmission rate cannot exceed 1 / T [bps], where the period of the spreading code is T [sec]. On the other hand, in the latter case, by increasing the number M of orthogonal spreading codes used, the information transmission rate can be set to (1 / T) log ₂ M [bps]. That is, this is the quadrature modulation method itself, and its transmission rate increases with an increase in the number (type) of codes, and the performance approaches the Shannon limit.

On the spread spectrum communication system,
Spread spectrum pulse position modulation, which has higher performance than off-keying method and does not require many matched filters like code shift keying method, and realizes receiving system with only one SAW matched filter. Japanese Patent Application Laid-Open No. 4-113732 discloses a (SS-PPM) communication system. This publication uses a pseudo noise sequence having a period L, and in a frame in which one frame is composed of M + 2L slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the L slot starting from a specific slot is used. Always inserts one cycle of the pseudo noise as a sync signal, and is L + 1 from the slot next to the last slot of the sync signal and from the first slot of the sync signal.
M in each frame corresponding to the slots before the slot
The pseudo noise of L slots starting from any one of them is inserted, the insertion slot position of the pseudo noise is made to correspond to the data symbol to be transmitted, and the consecutive frames are transmitted.

Further, the frame synchronization signal (pulse) is eliminated, the performance is improved, the frame synchronization circuit is omitted, and the circuit configuration is simplified. Further, the time for establishing the frame synchronization is minimized to prevent the occurrence of radio waves. Japanese Patent Application Laid-Open No. 4-137835 discloses a spread spectrum pulse position modulation (SS-PPM) communication system that enables use on a poor (unstable) transmission line. In this publication, a pseudo noise sequence having a period L is used, data symbols to be transmitted are M values, and one frame is M + L-.
In a frame consisting of 1 + j (j ≧ 0) slots,
The slot rate of the frame is the same as the chip rate of the pseudo noise sequence, the pseudo noise of L slot length starting from one of M slots from the beginning of the frame is inserted, and the insertion slot position of the pseudo noise is inserted. In accordance with the data symbol to be transmitted, the data symbol is differentially encoded, and the consecutive frames are transmitted.

[0005]

As described above, the conventional spread spectrum pulse position modulation communication system requires as many matched filters as the number of codes. This causes a problem of a large cost increase and an increase in size of the device. In recent years, the 2.4 GHz ISM band has S
Released to S communication system, SS
A spread spectrum pulse position modulation method has been proposed as a method capable of increasing the transmission rate without impairing the characteristics such as the anti-jamming property of the communication method. By the way, in the SS communication system which is a wide band modulation system, multipath propagation due to reflection and diffraction exists regardless of whether it is outdoors or indoors, and the cross correlation between direct and delayed waves causes adverse effects such as intersymbol interference in data determination. Since the spread spectrum pulse position modulation (SS-PPM) system proposed previously determines information by the position of the pulse which is the output of the matched filter,
It is affected under multipath fading.

The present invention has been made in view of the above circumstances, and divides a band to the extent that multipath fading does not occur, suppresses the transmission rate per channel, and instead uses a plurality of carriers having different frequencies. An object of the present invention is to provide an effective spread spectrum pulse position modulation method even under multipath fading by using the SS-PPM method for parallel high-speed transmission and a combination thereof with error correction coding.

[0007]

In order to solve the above problems, the present invention uses (1) a pseudo noise sequence having a period L, the data symbols to be transmitted are M values, and one frame is M + L- In a frame consisting of 1 + j (j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the pseudo slot having the L slot length starting from one of M slots from the beginning of the frame. Noise is inserted, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, the data symbol is differentially encoded, and the N frames are respectively modulated by N different carrier waves and added. The frames transmitted by each carrier wave are continuous, or (2) In the transmitter, M value data is input and the M value data is differentially encoded. , Using a pseudo-noise sequence of period L, 1
In a frame consisting of M + L-1 + j (j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the L slot starting from one of M slots from the beginning of the frame. The length of the pseudo noise is inserted, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, and the frame is set to N
The frames are sorted into sets, the N sets of frames are modulated with N different carriers, then added and transmitted, the frames transmitted on each carrier are continuous, and at the receiver,
The signal input from the transmission line is input to the N matched filters, the position of the output of the matched filters is determined, the corresponding data is decoded respectively, and the data obtained by decoding the N sets of data is received data. Or (3) In the transmitter, the data is transmitted in a predetermined bit (N
Serial / parallel conversion for each bit) and each bit string (1
To N columns) are each converted into M-valued data, then differentially encoded, and using a pseudo noise sequence having a period L, one frame is M
In a frame composed of + L-1 + j (j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the slot length of the L slot starting from one of M slots from the beginning of the frame. The pseudo noise is inserted, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, N sets of the frames are modulated by N different carrier waves, added and transmitted, and transmitted on each carrier. In the receiver, the signal input from the transmission line is input to the N matched filters, the positions of the outputs of the matched filters are determined, and the corresponding data are decoded and obtained respectively. The data obtained by performing parallel-serial conversion for each bit N sets of the N sets of M-value data are used as reception data, or (4) in the transmitter, the data are M-values. Data is converted, the M-value data is differentially encoded, a pseudo noise sequence having a period L is used, and in a frame in which one frame has M + L-1 + j (j ≧ 0) slots, the slot rate of the frame is the pseudo noise sequence. The pseudo-noise having the same chip rate as that of L-slot length starting from one of M slots from the beginning of the frame and making the insertion slot position of the pseudo-noise correspond to the data to be transmitted. Modulating the frames of the set with N different carriers, adding and transmitting,
The frames transmitted on each carrier are continuous, and in the receiver, the signal input from the transmission line is input to the N matched filters, the position of the output of the matched filters is determined, and the corresponding data are respectively received. Decoding and converting each of the N sets of M-value data into parallel-serial conversion data to be received data, and (5) In (3) or (4) above, the transmitter uses data for error correction. After encoding and bit interleaving, M value data is constructed by the above method, and the receiver judges the pulse position, deinterleaves the decoded M value data, and receives the error-corrected data. The feature is that it is data.

[0008]

According to the spread spectrum pulse position modulation communication system of the present invention having the above-mentioned structure, (1) a pseudo noise sequence having a period L is used, data symbols to be transmitted are M values, and one frame is M + L-1 + j ( In a frame consisting of j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the pseudo noise of L slot length starting from one slot of M from the beginning of the frame is And inserting the pseudo-noise insertion slot position corresponding to the data to be transmitted, the data symbol is differentially encoded, and the N frames are different from each other in N.
Each carrier is modulated, added and transmitted, and the frames transmitted on each carrier are made continuous.
A spread spectrum pulse position modulation method effective under multipath fading can be provided.

(2) In the transmitter, M-valued data is input, the M-valued data is differentially encoded, a pseudo noise sequence having a period L is used, and one frame is M + L-1 + j (j
≧ 0) slot, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the pseudo noise of L slot length starting from one of M slots is inserted from the beginning of the frame. Then, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, the frames are distributed to N sets, the N sets of frames are modulated with N different carrier waves, and then added and transmitted. The frames transmitted on each carrier wave are continuous, and the receiver receives N signals from the transmission path.
The data is input to the matched filters, the position of the output of the matched filters is determined, the corresponding data is decoded respectively, and the data obtained by decoding the N sets of data in the distributed order is set as the received data. Therefore, under multipath fading, A transmission / reception system of an effective spread spectrum pulse position modulation system can be provided.

(3) In the transmitter, the data is serial-parallel converted for each predetermined bit (N bits), each converted bit string (1 to N columns) is converted into M-value data, and then the differential code is applied. In a frame in which one frame consists of M + L-1 + j (j ≧ 0) slots using a pseudo noise sequence having a period L, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and from the beginning of the frame The pseudo noise having an L slot length starting from one of the M slots is inserted, the insertion slot position of the pseudo noise is made to correspond to data to be transmitted, and N sets of the frames are set to N different carriers. The frames transmitted by each carrier are continuous, and the signal input from the transmission line is input to the N matched filters in the receiver. , The position of the output of the matched filter is determined, the corresponding data is decoded respectively, and the data obtained by performing parallel-serial conversion for each bit N sets of the obtained N sets of M-value data is used as the reception data. It is possible to provide a transmission / reception system of a spread spectrum pulse position modulation method which is effective under fading.

(4) In the transmitter, the data is converted into M value data, the M value data is differentially encoded, and the period L
1 frame is M + L-1 + j using the pseudo noise sequence of
In a frame consisting of (j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo-noise sequence, and the pseudo-noise having an L slot length starting from one of M slots from the beginning of the frame. Is inserted, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, the N sets of the frames are modulated by N different carriers, added and transmitted, and transmitted on each carrier. The frames are continuous, and in the receiver, the signal input from the transmission path is input to the N matched filters, the positions of the outputs of the matched filters are determined, and the corresponding data are decoded respectively. Since the data obtained by performing parallel-serial conversion for each M-value data is used as the data to be received, it is possible to provide a transmission / reception system configured with one differential encoder.

(5) In the transmitter, the data is encoded for error correction, bit interleaved, and then the M value data is constructed by the above method. In the receiver, the pulse position is judged and decoded. Since M-value data is deinterleaved and error-corrected data is used as received data,
It is possible to provide a more effective spread spectrum pulse position modulation method under multipath fading.

[0013]

Embodiments will be described below with reference to the drawings. First, spread spectrum pulse position modulation method (SS
-PPM) will be described. FIG. 1 is a diagram illustrating a signal configuration example of SS-PPM. In the example of FIG. 1, SS-PP
The M signal is composed of a frame having a (M + L-1) slot length, one spread code (pseudo spread code) having an L chip length is present in each frame, and information is transmitted depending on the position of the spread code. Is.

FIG. 2 is a block diagram of an SS-PPM transmission / reception system, in which 1 is input data, 2 is a transmitter, and 3 is.
Is a log ₂ Mbit / 1 frame, 4 is a DPPM pulse generator, 5 is a switcher, 6 is a PN signal generator, 7 is a multiplier, 8
Is an fc frequency generator, 9 is a channel, 10 is a receiver,
11 is a multiplier, 12 is an fc frequency generator, 13 is a PN matched filter, 14 is a pulse position detector, and 15 is output data.

At the transmitter, the data is divided into log ₂ M bits and input to the differential coded pulse position generator (DPPM) 4. The DPPM 4 differentially encodes continuous log ₂ M-bit data, and generates a pulse at a corresponding frame position based on the obtained data. With this pulse as a trigger, the PN signal generator 6 outputs an L chip spread code. Then, this signal is multiplied by the carrier wave fc and transmitted.

The received signal is input to the same PN matched filter 13 as the spreading code used on the transmitting side. here,
When the input spread code pattern and the pattern of the PN matched filter 13 match, a pulse for one chip section is output. Since the position of the pulse is output to the slot corresponding to the transmission information in the frame M slot, the position of the pulse of the output is determined and the corresponding data is used as the reception data.

The positions of the pulses are the i-th frame and the (i +) th frame.
1) It can be determined as follows from the pulse interval P _{i of the} frame. The continuous M-value data before differential encoding is S ′.
_{If i} and S ′ _{i + 1} , the differentially encoded data S _i is S _i = S ′ _{i + 1} −S ′ _i (moduloM) (1). Since one frame length is M + L-1 + j slots, P _i = (M + L-1 + j) + S _i (2). Therefore, S _i = P _i − (M + L−1 + j) = P _i − (L−1 + j) (modulo M) (3), and the data S _i is demodulated by measuring the pulse interval P _i .

By the way, the SS-PPM system has high frequency utilization efficiency, but as described above, since information is determined by the pulse position which is the output of the PN matched filter 13, it is weak against multipath fading. On the other hand, as a method to prevent multipath fading, the band is divided to the extent that multipath fading does not occur, the transmission rate per channel is suppressed, and instead, high-speed transmission is performed in parallel using multiple carriers with different frequencies. Carrier modulation schemes are under consideration. The first aspect is to improve the characteristics under multipath fading by converting the SS-PPM system into multiple carriers.

3 and 4 are block diagrams of the transmission / reception system of this embodiment. FIG. 3 shows a transmission system and FIG. 4 shows a reception system. In the figure, 21 is an S / P (serial / parallel converter), 22-1 to 22-n are transmitters, and 23-1 to 23-n are DPs.
PM pulse generator, 24-1 to 24-n are switching devices, 25-1 to
25-n is a PN signal generator, 26-1 to 26-n are multipliers, 2
7 is an adder, 28 is a transmitting antenna, 31 is a receiving antenna, 32-1 to 32-n are receivers, 33-1 to 33-n are multipliers, 34-1 to 34-n are PN matched filters, and 35 -1 ~
Reference numeral 35-n is a pulse position detector, and 36 is a P / S (parallel-serial converter).

On the transmitting side, the data symbol is serial-parallel converted every N bits, and each converted bit string (1 to N strings) is converted.
The data is divided into log ₂ M bits and input to the differential encoding pulse position generators (DPPM) 23-1 to 23-n. Each D
In PPMs 23-1 to 23-n, continuous log ₂ M-bit data is differentially encoded, and each PN is triggered by a pulse generated at a position of a corresponding frame based on the obtained data.
Spreading codes of L chips are output from the signal generators 25-1 to 25-n. The output N frames are multiplied by different carrier frequencies (f _c1 , f _c2 , ..., F _cn ), and then added and transmitted. At this time, each frequency band is divided to the extent that multipath fading does not occur, and
In the DPPMs 23-1 to 23-n, the spreading code length and the frame length are adjusted so that the frames are continuous.

On the receiving side, after the received signal is dropped to the baseband, it is input to the PN matched filters 34-1 to 34-n and the peak pulse positions of the outputs of the PN matched filters 34-1 to 34-n are determined. judge. The pulse position can be determined by measuring successive pulse intervals as described above. The corresponding M-value data is decoded from the position of this pulse, and the obtained N sets of M-value data are subjected to parallel-serial conversion for each N sets of bits to be demodulated data.

Next, the invention according to claim 2 will be described. FIG. 5 is a block diagram of the transmission system of the present embodiment, in which 41 is an S / P (serial / parallel converter), 42-1
42-n are transmitters, 43-1 to 43-n are DPPM pulse generators, 44-1 to 44-n are selectors, and 45-1 to 45-n are PNs.
Signal generator, 46-1 to 46-n are multipliers, 47 is an adder,
Reference numeral 48 is a transmission antenna.

The M-value data input to the transmitter is N sets of differentially coded pulse position generators (DPPM) 43-1 to 43-43.
-n is input sequentially. In each DPPM 43-1 to 43-n,
Differential encoding is performed on the continuous M-value data by differential encoding, a pulse is generated at the position of the corresponding frame based on the data, and the PN signal generator outputs an L-chip spreading code using this pulse as a trigger. The output N sets of frames are multiplied by different carriers (f _c1 , f _c2 , ..., F _cn ), and then added and transmitted. At this time, divide each frequency band to the extent that multipath fading does not occur,
Alternatively, in each DPPM, the spread signal length and frame length are adjusted so that the frames are continuous.

FIGS. 6 and 7 are diagrams showing an example of a receiving system of this embodiment. In the figure, 51 is a receiving antenna, 52-1
52-n are receivers, 53-1 to 53-n are multipliers, 54-1 to
54-n is a PN multi-filter, 55-1 to 55-n are pulse position detectors, 56 is a P / S (parallel-serial converter), 61 is a receiving antenna, 62-1 to 62-n are receivers,
63-1 to 63-n are PN matched filters, 64-1 to 64
-n is an envelope detector, 65-1 to 65-n are pulse position detectors, and 66 is a P / S (parallel-serial converter).

In the embodiment of FIGS. 6 and 7, after the received signal is dropped to the base band, the PN matched filters 54-1 to 54-1.
54-n, and the PN matched filters 54-1 to 54
-The pulse position of the peak of the output of n is judged. Also, FIG.
In the embodiment shown in FIG. 6, after the received signal is input to the PN matched filters 63-1 to 63-n, the envelope detectors 64-1 to 64-n are input.
Envelope detection is performed with to determine the pulse position of the output value. The pulse position can be determined by measuring successive pulse intervals as described above. Data corresponding to the M value is demodulated from the position of the pulse, and N sets of data are subjected to parallel / serial conversion in the distributed order to obtain demodulated data.

Next, the invention according to claim 3 will be described. FIG. 3 is a diagram showing an example of a transmission system of this embodiment. Data symbols are converted serially to parallel every N bits,
Each bit string (1-N string) after conversion is divided into log ₂ M bits, and N sets of differentially encoded pulse position generators (DPPM)
23-1 to 23-n respectively. Each DPPM 23-1
23 to 23-n, PN signal generators 25-1 to 25-n 25-1 to 25-n each of which is configured to differentially encode continuous log ₂ M-bit data and use a pulse generated at a corresponding frame position as a trigger based on the obtained data. Outputs the spread code of L chips.
A different carrier (f
_c1 , f _c2 , ..., F _cn ) are multiplied, then added and transmitted. At this time, each frequency band is divided to the extent that multipath fading does not occur, and each DPPM 23-1 to 2
In 3-n, the spreading code length and frame length are adjusted so that the frames are continuous.

4 and 8 are diagrams showing an example of a receiving system of this embodiment. In the embodiment of FIG. 4, after dropping the received signal to the baseband, the PN matched filters 34-1 to 34-3 are used.
4-n to input the PN matched filters 34-1 to 34-n
Determine the pulse position of the output peak. Further, in the embodiment shown in FIG. 8, the received signal is processed by the PN matched filter 7
After inputting to 3-1 to 73-n, envelope detectors 74-1 to 74-n perform envelope detection to determine the pulse position of the output value. The pulse position can be determined by measuring successive pulse intervals as described above. The corresponding M-value data is decoded from the obtained pulse position, and the obtained N sets of M-value data are subjected to parallel-serial conversion for each N sets of bits to be demodulated data.

Next, the invention according to claim 4 will be described. FIG. 9 is a block diagram of the transmission system of the present embodiment. In the figure, 81 is log ₂ Mbits / one frame, 82 is a differential encoder, 83 is S / P, and 84-1 to 84-n are transmissions. Machine, 85-1
~ 85-n is a PPM pulse generator, 86-1 to 86-n is a switcher, 87-1 to 87-n is a PN signal generator, 88-1 to 88-n
Is a multiplier, 89 is an adder, and 90 is a transmission antenna.

Data symbols are differentially encoded by M values for each log ₂ M bits, and then N sets of pulse position generators (PPM P
ulse) sequentially. Each pulse position generator 85-1 to 8
In 5-n, each PN signal generator 8 is triggered by the pulse generated at the position of the corresponding frame based on the input data.
Spread codes of L chips are output from 7-1 to 87-n. The output N sets of frames are multiplied by different carriers (f _c1 , f _c2 , ..., F _cn ), and then added and transmitted. At this time, each frequency band is divided to the extent that multipath fading does not occur, and in each DPPM, the spread code length and frame length are adjusted so that the frames are continuous. According to the third aspect, N sets of differential encoders are required, but the transmission system of the present embodiment can be configured with one differential encoder 82.

FIG. 4 and FIG. 8 are diagrams showing an example of a receiving system of this embodiment. In the embodiment of FIG. 4, after dropping the received signal to the baseband, the PN matched filters 34-1 to 34-3 are used.
4-n to input the PN matched filters 34-1 to 34-n
Determine the pulse position of the output peak. Further, in the embodiment shown in FIG. 8, the received signal is processed by the PN matched filter 7
After inputting to 3-1 to 73-n, envelope detectors 74-1 to 74-n perform envelope detection to determine the pulse position of the output value. The pulse position can be determined by measuring successive pulse intervals as described above. The corresponding M-value data is decoded from the obtained pulse position, and the data obtained by performing parallel-serial conversion for each of the obtained N sets of M-value data is used as demodulation data.

Next, the invention according to claim 5 will be described. 10 to 12 are configuration diagrams of the transmission / reception system of the present embodiment. FIG. 10 shows a transmitter, and FIGS. 11 and 12 show a receiver. In the figure, 91 is an encoder, 92 is an interleaver, and 9
3 is S / P (serial / parallel converter), 94-1 to 94
-n is a transmitter, 95-1 to 95-n are DPPM pulse generators,
96-1 to 96-n are switching devices, 97-1 to 97-n are PN signal generators, 98-1 to 98-n are multipliers, 99 is an adder, 100
Is a transmitting antenna, 101 and 111 are receiving antennas, 10
2-1 to 102-n, 112-1 to 112-n are receivers, 103
-1 to 103-n are multipliers, 104-1 to 104-n, 113-1
~ 113-n are PN matched filters, 105-1 to 105
-n, 115-1 to 115-n are pulse position detectors, 106,
116 is P / S, 107 and 117 are deinterleaver, 1
Reference numerals 08 and 118 are decoders, and 114-1 to 114-n are envelope detectors.

10 to 12 show the case where the method described in claim 3 is used as the spread spectrum pulse position modulation method. On the transmitting side, the data is encoded for error correction, interleaved by an interleaver 92, M-value data is constructed by the methods of claims 3 and 4, and spread spectrum pulse position modulation is performed for transmission. On the receiving side,
The M-value data decoded by each method is deinterleaved by the deinterleavers 107 and 117 to perform error correction,
This is the received data. This can reduce the influence of errors that occur under frequency fading.

[0033]

As is apparent from the above description, the present invention has the following effects. (1) Effect corresponding to claim 1: A spread spectrum pulse position modulation method effective under multipath fading can be provided. (2) Effect corresponding to claim 2: A transmission / reception system of a spread spectrum pulse position modulation system effective under multipath fading can be provided. (3) Effect corresponding to claim 3: It is possible to provide a transmission / reception system of a spread spectrum pulse position modulation method effective under multipath fading. (4) Effect corresponding to claim 4: It is possible to provide a transmission / reception system including one differential encoder. (5) Effect corresponding to claim 5: A more effective spread spectrum pulse position modulation method can be provided under multipath fading.

[Brief description of drawings]

FIG. 1 is a diagram showing a signal configuration example of a spread spectrum pulse position modulation communication system according to the present invention.

FIG. 2 is a configuration diagram of a transmission / reception system of a spread spectrum pulse position modulation communication system according to the present invention.

FIG. 3 is a configuration diagram of a transmission system of a spread spectrum pulse position modulation communication system according to the present invention.

FIG. 4 is a configuration diagram of a receiving system of a spread spectrum pulse position modulation communication system according to the present invention.

FIG. 5 is a configuration diagram of another transmission system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 6 is a configuration diagram of another receiving system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 7 is a configuration diagram of still another receiving system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 8 is a configuration diagram of still another receiving system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 9 is a configuration diagram of still another transmission system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 10 is a configuration diagram of still another transmission system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 11 is a configuration diagram of still another receiving system of the spread spectrum pulse position modulation communication system according to the present invention.

FIG. 12 is a configuration diagram of still another receiving system of the spread spectrum pulse position modulation communication system according to the present invention.

[Explanation of symbols]

1 ... Input data, 2 ... Transmitter, 3,81 ... log ₂ Mbits / one frame, 4 ... DPPM pulse generator, 5 ... Switching section, 6 ... PN signal generator, 7 ... Multiplier, 8 ... fc generation Unit, 9 ... Channel, 10 ... Receiver, 11 ... Multiplier, 1
2 ... fc generator, 13 ... PN matched filter, 14 ...
Pulse position detector, 15 ... Output data, 21, 41, 8
3, 93 ... S / P (serial / parallel converter), 22-1
~ 22-n, 42-1 ~ 42-n, 84-1 ~ 84-n, 94-1 ~
94-n ... Transmitter, 23-1 to 23-n, 43-1 to 43-n, 9
5-1 to 95-n ... DPPM pulse generator, 24-1 to 24-
n, 44-1 to 44-n, 86-1 to 86-n, 96-1 to 96-n
... Switching device, 25-1 to 25-n, 45-1 to 45-n, 87-1 to
87-n, 97-1 to 97-n ... PN signal generator, 26-1 to 2
6-n, 33-1 to 33-n, 46-1 to 46-n, 53-1 to 53
-n, 88-1 to 88-n, 98-1 to 98-n, 103-1 to 10
3-n ... Multiplier, 27, 47, 89, 99 ... Adder, 2
8, 48, 90, 100 ... Transmitting antennas, 31, 51,
61, 71, 101, 111 ... Receiving antenna, 32-1 ...
32-n, 52-1 to 52-n, 62-1 to 62-n, 72-1 to 7
2-n, 102-1 to 102-n, 112-1 to 112-n ... Receiver, 34-1 to 34-n, 54-1 to 54-n, 63-1 to 63-
n, 73-1 to 73-n, 104-1 to 104-n, 113-1 to
113-n ... PN matched filter, 35-1 to 35-n, 5
5-1 to 55-n, 65-1 to 65-n, 75-1 to 75-n, 10
5-1 to 105-n, 112-1 to 112-n ... Pulse position detector, 36, 56, 66, 76, 106, 116 ... P / S
(Parallel to serial converter), 64-1 to 64-n, 74-1
~ 74-n ... Envelope detector, 82 ... Differential encoder, 85-1
-85-n ... PPM pulse generator, 91 ... Encoder, 92
... interleaver, 107,117 ... deinterleaver, 1
08, 118 ... Decoder.

Claims (5)

[Claims] 1. A pseudo noise sequence having a period L is used, data symbols to be transmitted are M values, and one frame is M + L.
In a frame consisting of −1 + j (j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the slot length of the L slot starting from one of the M slots from the beginning of the frame. Pseudo noise is inserted, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, the data symbols are differentially encoded, and the N frames are respectively modulated by N different carrier waves and added. The spread spectrum pulse position modulation communication method is characterized in that the frames transmitted by each carrier are continuous. 2. The transmitter receives M value data, differentially encodes the M value data, uses a pseudo noise sequence having a period L, and one frame has M + L-1 + j (j ≧ 1).
0) In a frame consisting of slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the pseudo noise of L slot length starting from one slot of M is inserted from the beginning of the frame. , The pseudo noise insertion slot position is made to correspond to the data to be transmitted, the frames are distributed to N sets, the N sets of the frames are modulated by N different carrier waves, and then added and transmitted, The frames transmitted on the carrier wave are continuous, and the signal input from the transmission line is received by the receiver at N
Spread spectrum inputting to each matched filter, determining the position of the output of the matched filter, decoding the corresponding data, and decoding the N sets of data in the distributed order as received data Pulse position modulation communication system. 3. In the transmitter, data is serial-parallel converted for each predetermined bit (N bits), each converted bit string (1 to N strings) is converted into M value data, and then differential encoding is performed. , Using a pseudo-noise sequence of period L, in a frame in which one frame consists of M + L-1 + j (j ≧ 0) slots, the slot rate of the frame is the same as the chip rate of the pseudo-noise sequence, and M
The pseudo noise having an L slot length starting from one of the slots is inserted, the insertion slot position of the pseudo noise is made to correspond to the data to be transmitted, and the N sets of the frames are arranged on N different carrier waves. The frames that are modulated, added, and transmitted, and transmitted on each carrier are continuous, and in the receiver, the signal input from the transmission line is input to the N matched filters, and the position of the output of the matched filters is input. And the corresponding data are respectively decoded, and the data obtained by performing parallel-serial conversion for each bit N sets of the obtained N sets of M-value data are used as reception data. . 4. A transmitter converts data into M-valued data, differentially encodes the M-valued data, and uses a pseudo noise sequence having a period L, so that one frame is M + L-1 + j (j ≧ 1).
0) In a frame consisting of slots, the slot rate of the frame is the same as the chip rate of the pseudo noise sequence, and the pseudo noise of L slot length starting from one slot of M is inserted from the beginning of the frame. , The pseudo-noise insertion slot position is made to correspond to data to be transmitted, N sets of the frames are modulated by N different carrier waves, added and transmitted, and the frames transmitted on each carrier are continuous. Then, in the receiver, the signal input from the transmission line is input to N matched filters, the positions of the outputs of the matched filters are determined, and the corresponding data are decoded respectively, and N sets of M-value data are output. A spread spectrum pulse position modulation communication system characterized in that data obtained by parallel-serial conversion is used as received data. 5. The transmitter performs error correction coding on the data, performs bit interleaving, forms M value data by the above method, and determines M and decodes the pulse position at the receiver. 5. The spread spectrum pulse position modulation communication system according to claim 3, wherein the value data is deinterleaved and the error-corrected data is used as received data.