JPH03153137A - Pulse location modulation communication equipment - Google Patents

Abstract

PURPOSE:To attain multiplex communication by superimposing a transmission signal onto a pseudo noise signal at a transmitter side and eliminating the noise component at a receiver side through the inverse correlation processing using the same pseudo noise signal representing a large correlation. CONSTITUTION:A mixer 6 of a transmitter 1 applies multiplication modulation to a known pseudo noise signal from a pseudo noise generator 5 and the result is inputted to a pulse location modulator 4, from which the resulting signal is sent through a transmission line 3 as a pulse location modulation signal with a pseudo noise signal. A receiver 2 is provided with a pulse location demodulator 7 demodulating a pulse location modulation signal sent through the transmission line 3 into the original transmission and the pseudo noise signal, a pseudo signal generator 8 and an inverse correlation device 9, which takes inverse correlation with the same pseudo noise signal as that at the transmitter and obtains a transmission signal being a demodulation signal. Each transmission/reception system uses a different pseudo noise signal to specify a relevant transmission/reception system, the synchronization of the entire system is not required and multiplication is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a pulse position modulation communication device used in the field of telecommunications, radio wave communication or optical communication.

2. Description of the Related Art Conventionally, when multiplexing communications using a pulse position modulation method, a time division method has been mainly used because a frequency division method is not suitable because the pulse band is wide.

Problems to be Solved by the Invention Although this method is effective for packet communication, in situations such as wireless communication where the system is constantly exposed to external noise and it is not known when this noise signal will enter, the entire system becomes It is difficult to synchronize and lacks flexibility, making it difficult to apply.

Means for solving the problem includes a pseudo-noise generator, a mixer, and a pulse position modulator,
A transmitter that primary modulates a transmission signal using a pseudo noise signal from a pseudo noise generator in a mixer, and then generates and transmits a pulse position modulated signal using a pulse position modulator, a pulse position demodulator, and a pseudo noise generator. After the received pulse position modulated signal is demodulated by the pulse position demodulator, it is transmitted by anti-correlation processing of the anti-correlator using the same pseudo noise signal as that on the transmitter side. It consists of a receiver that demodulates the signal.

Effect: The transmitter side superimposes a pseudo-noise signal onto the transmitted signal, and the receiver side removes the noise component by performing anti-correlation processing using the same pseudo-phase signal that shows a large correlation. Although it is a pulse position modulation method,
3'), by simply using different pseudophases 1 and 7 in the receiving system, multiple Φ: communications can be performed without synchronizing the entire system.
Becomes No.1. At this time, since the receiver side requires the same pseudo-phase tone signal as the transmitter side, privacy of the communication is also ensured.

That is, in addition to the conventional pulse position modulation method, the code division method represented by the direct spread method as shown in Japanese Patent Application Laid-Open No. 53-257344, for example, as one of the multiple IR methods, can be effectively added. It is used in combination with combination ce.

Example An embodiment of the present invention will be explained based on the drawings.

First, FIG. 1 shows the basic configuration, in which a transmitter 1 and a receiver 2 are coupled by a transmission path 3.

Here, the transmitter 1 has a pseudo phase N in addition to the pulse position modulator 4.
'1. Equipped with a generator 5 and a mixer 6, the mixer 6 multiplies and modulates the transmission signal with a known pseudo-noise signal from the pseudo-noise generator JU device 5. After l- (primary modulation), the pulse is The position modulator 4 is manually operated to generate a pulse position modulation signal carrying a pseudo-miscellaneous r''? signal, and the signal is transmitted through the transmission path 3.

The transmission path 3 may be a cable or space, and the transmission medium may be electricity (radio waves), light, or sound.

The receiver 2 converts the pulse position modulated signal ~ transmitted via the transmission line 3 into the original transmission signal and the pseudo phase (S'- signal). Pd (,1
”, S. 3. That is, the same (
The noise component is removed by taking advantage of the fact that only ``Yan'II'' shows a large correlation of -4. At this time, I
The signals from the t-station, thermal noise, etc. have a small correlation, so they hardly appear in the output. Therefore, consider the pulse position change 1m'1 method.
However, by using different pseudo-noise signals in each transmitting and receiving system, it becomes possible to specify the transmitting and receiving system that corresponds to R, and multiplexing can be performed without the need to synchronize the entire system. In this case, various code sequences typified by the M sequence can be used for the pseudo-phase tone signal J. Furthermore, since the receiver 2 side requires the same pseudo-phase tone signal 3- as the transmitter l side, privacy of the communication is also ensured. Furthermore, transmission uses pulses, and especially in optical communication systems, the transmission distance can be extended by reducing the peak power.

, ′, 1″′, if the digital data signal is transmitted through the event hole, σ) transmission (a ifQ% I is shown in Fig. 2). Field n・, %1
14:;t at, R, Ihashi: Also pseudo digital female 5
'f communication (; and, '5J1..1ri similar (Nl'5 '
ff 4'li 'tE' - is generated in response to the transmitting clock i- and i clock from the clock generator 11.

,'', these digital data signals and pseudo digital noise signals to be transmitted are input to the [ ) type flip-flop 13 through the exclusive OR gate 12, and are subjected to superimposition modulation processing corresponding to the mixer 6. A monostable multi-pipe 1 notator 14 is provided that emits pulses at regular intervals in accordance with the transmitting clock from the clock generator 11.The output of this monostable multi-vib 1 notor 14 is the delay circuit 1
The 3-state buffer 16.17 is divided into two systems, one that does not include 5 and the other that includes 5, and has a difference in pulse position between the two systems, and each operates according to the outputs Q and Q of the IT stable multivibrator 4. is used to select only the output of one system to obtain a modulated signal that is a code-divided pulse position modulated signal.

That is, the monostable multivibrator 14, the delay circuit 15, and the 3-state buffers 16 and 17 form the pulse position modulator 4.
corresponds to

Next, a specific example of the configuration of the receiver 2 will be explained with reference to FIG. First, the transmitted received signal (modulation No. 1.1) is divided into two systems depending on the presence or absence of the delay circuit 18, and each is input to the sample and hold circuits 19 and 20. For this sampling, a receiving side clock generated by a clock generator 21 exhibiting high stability is used so that sampling is performed at the peak position of the received signal pulse. These delay circuit 18 and sample & hold circuits 19 and 20 correspond to the pulse position demodulator 7. The outputs (signal series) of the sample and hold circuits 19 and 20 of each of the two systems are sent to the pseudo noise generator 22.
Convolver 23.24 with pseudo-noise signal sequence from
The inner product is calculated. These convolvers 23 and 24 are realized by surface acoustic wave devices, CCDs, MOSs, or the like. The outputs of these convolvers 23 and 24 are input to an operational amplifier 25. Here, since the convolvers 23 and 24 output only one of the desired station signals, 0 and 1, the demodulated signal output from the operational amplifier 25 will be the desired station signal when the desired station signal is 1 (+), and the desired station signal. signal is O
When the desired station is not transmitting, it is demodulated as (-), and when the desired station is not transmitting, it is demodulated as (0). That is, the convolvers 23 and 24 and the operational amplifier 25 correspond to the anti-correlator 9.

However, regarding such a receiver 2 configuration.

As shown in FIG.
It may be simplified as 8. In this case, convolver 2
The output of 8 becomes the demodulated signal as it is.

On the other hand, the receiver 2 may have a circuit configuration that uses a delay lock loop to generate the receiving side clock. FIG. 5 shows an example of this. First, the received signal is input to Δ
A delay circuit 29 is provided, the delayed output of which is input to an adder 30 together with the directly received signal. Here, it is shown that the delay amount Δ of the Δ delay circuit 29 is the same as the delay amount caused by the delay circuit 15 on the transmitter 1 side. And adder 30
The output is divided into three systems. In the first system, the signal is directly input to the sample & hold circuit 31 (delay 10) and output to the convolver 32. In the second system, after being delayed by the δ/2 delay circuit 33, the signal is input to the sample & hold circuit 34 and output to the convolver 35. In the third system, after being delayed by the δ delay circuit 36, the signal is input to the sample & hold circuit 37 and output to the convolver 38. δ indicates the number 1 pulse width. A pseudo noise generator 22 is commonly connected to the convolvers 32, 35, 38. Here, the difference between the outputs of the convolvers 32 and 38 of the first system with a delay time O and the third system with a delay time δ exhibits a figure-8 characteristic that is point symmetrical with respect to the delay time δ/2 of the second system. Therefore, by adding the outputs of the convolvers 32 and 38 using an adder 39 and using this as a control signal to drive the voltage controlled oscillator 41 through the loop filter 40, a clock synchronized with the received signal can be obtained. Therefore, the sample & hold circuits 31, 34, 37 and the pseudo noise generator 22 are controlled by the output (Glock) of the voltage controlled oscillator 41, and a demodulated signal is obtained from the convolver 35 of the second system.

FIG. 6 is a timing chart showing each signal state according to the configurations of FIGS. 2 and 5. FIG.

Effects of the Invention The present invention is configured as described above, and the transmitter side superimposes a pseudo-noise signal on the transmission signal, and the receiver side performs anti-correlation processing using the same pseudo-noise signal that has a large correlation with the transmitted signal. Since the noise component is removed, multiplex communication is possible without synchronizing the entire system by simply using different pseudo-noise signals in each transmitting and receiving system, even though the pulse position modulation method is used. 1) A simple configuration is required, and at this time, since the receiver side requires the same pseudo-noise signal as the transmitter side, it is possible to ensure the privacy of the communication terminal 11.

8. I' adjuster, pseudo noise generator, Co., Ltd. 9... Reverse sum opener

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a block diagram showing the present configuration, FIG. 2 is a block diagram showing an example of the transmitter configuration, and FIG. 3 is an example of the receiver configuration. Fig. 4 is a block diagram showing an example of the receiver configuration; Fig. 5 is a block diagram showing an example of the receiver configuration;
FIG. 6 is a block diagram showing the other side of the receiver configuration.
The figure is a timing chart. ■...Transmitter, 2...94.1 machine, 4...Pulse position modulator, 5...Pseudo noise generator, 6...Mixer,
7. Pal-Atsushi 3 Bacteria-Fig.

Claims (1)

[Claims] It has a pseudo noise generator, a mixer, and a pulse position modulator,
A transmitter that generates and transmits a pulse position modulated signal by a pulse position modulator after primary modulating a transmission signal with a pseudo noise signal from a pseudo noise generator in a mixer, a pulse position demodulator, and a pseudo noise generator. After demodulating the received pulse position modulated signal with the pulse position demodulator, the transmitted signal is demodulated by anti-correlation processing of the anti-correlator using the same pseudo-noise signal as that on the transmitter side. A pulse position modulation communication device consisting of a receiver.