JPH05219009A - Spread spectrum communication device - Google Patents

Abstract

PURPOSE:To enable a multiplexed communication wherein mutual interference is small by assigning a dummy noise code to slave equipment to have a communication in the decreasing order of correlation characteristics. CONSTITUTION:The slave equipment 1 is not previously given the dummy noise code, and given the dummy noise code in the decreasing order of the correlation characteristics by a dummy noise code storage part 12 when making a communication. The slave equipment 1 which is given the dummy noise code imposes spread spectrum modulation on a speech signal and sends it by radio. A connection device 5 imposes spread spectrum demodulation upon the received signal and sends the speech signal through a cable transmission line 7. A controller 8 switches and outputs the speech signal, inputted from the connection device 5, to the cable transmission line 7 connected to a connection device 5 which can make a communication with another slave equipment 1 specified by a control part 9 at the time of slave equipment transmission. Then the connection device 5 which inputs the speech signal from the controller 8 through the cable transmission line 7 imposes spread spectrum modulation on the speech signal and sends it by radio. The specified slave equipment is given the dummy noise code by the dummy noise code storage part 12 in the decreasing order of the correlation characteristics.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spread spectrum communication device having a control device, a plurality of slave units, and a plurality of connection devices.

[0002]

2. Description of the Related Art In recent years, spread spectrum communication devices have come to be used not only for military communication but also for public communication and personal communication because they are excellent in multiple access, confidentiality and interference resistance. ..

A conventional spread spectrum communication device will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of a conventional spread spectrum communication device. In the figure, 1 is a slave unit, 2
Is a slave antenna, 3 is an SS modulator for spread spectrum modulating an audio signal, 4 is an SS demodulator for spread spectrum demodulating to obtain an audio signal, 5 is a connection device, 6 is a connection device antenna, 8 is a control device, 7 Is a wired transmission line for transmitting an audio signal between the control device 8 and the connection device 5, 10 is a line, 11
Is a telephone, and 9 is a control unit for switching control so as to transmit and receive voice signals to and from the plurality of connection devices 5 and the telephone 11.

With respect to the conventional spread spectrum communication apparatus composed of the above constituent elements, the relationship and operation of each constituent element will be described below.

The slave unit 1 spread-spectrum-modulates the voice signal input by the microphone or the like in the SS modulator 3,
The handset antenna 2 transmits as a radio wave. Connection device 5
Receives the radio wave from the cordless handset 1 by the connection device antenna 6 and then converts it into a frequency band modulated by the SS modulator 3 of the cordless handset 1, and performs spread spectrum demodulation by the SS demodulator 4 to transmit a voice signal. It is output to the control device 8 via the wired transmission line 7. In the control device 8, the control unit 9 switches to the wired transmission path 7 connected to the connection device 5 capable of communicating with another slave device 1 designated at the time of transmitting the slave device in response to the audio signal input from the connection device 5. Output. Alternatively, when the telephone 11 connected by wire is designated at the time of transmitting the slave unit, the voice signal is switched to the line 10 and output. Next, in the connection device 5 to which the audio signal from the control device 8 is input via the wired transmission path 7, the audio signal is spread-spectrum-modulated in the SS modulator 3 as in the case of the slave unit 1, and then the connection is established. Radio waves converted into a radio frequency band are transmitted from the device antenna 6. The designated slave unit 1 converts the frequency band in the same manner as when the slave unit antenna 2 receives the radio wave from the connection unit 5, and then the connection unit receives the radio wave, and the SS demodulation unit 4 performs spread spectrum demodulation to perform voice conversion. The signal is demodulated and output to a speaker or the like. In this way, between a plurality of cordless handsets or cordless handset 1 and telephone 1
Voice communication between the two becomes possible.

[0007]

However, in the above-described conventional spread spectrum communication device, since the pseudo noise code is assigned to the slave units in advance, the correlation characteristic between the pseudo noise codes is poor when the number of slave units increases. A case arises,
There is a problem that mutual interference between signals becomes large.

An object of the present invention is to solve the above problems and to provide a spread spectrum communication device with less mutual interference between signals.

[0009]

In order to achieve the above object, the present invention has a structure in which a pseudo noise code storage unit for storing pseudo noise codes in order of good correlation characteristics is provided in a control device.

[0010]

With the above-described structure, the present invention operates so that pseudo noise codes are assigned to the handsets that perform a call in order of good correlation characteristics.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the spread spectrum communication apparatus of this embodiment. In FIG. 1, 1 is a slave unit, 2 is a slave unit antenna, 3 is an SS modulator that spread-spectrum-modulates a voice signal, 4 is an SS demodulator that obtains a voice signal by spread-spectrum demodulation, 5 is a connection device, and 6 is a connection A device antenna, 8 is a control device, 7 is a wired transmission line for transmitting an audio signal between the control device 8 and the connection device 5, 10 is a line, 11 is a telephone, 9 is a plurality of connection devices 5 and 11 A control unit that controls switching so that voice signals are transmitted and received between them, and a pseudo noise code storage unit 12 that stores pseudo noise codes in order of good correlation characteristics.

With respect to the spread spectrum communication apparatus including the above-mentioned components, the relationship and operation of each component will be described below. Unlike the conventional example, the handset 1 is not given a pseudo-noise code in advance, and the pseudo-noise code storage unit 12 gives the pseudo-noise code in order of good correlation characteristics when making a call. The slave 1 to which the pseudo-noise code is assigned operates in the same manner as in the conventional example, spread-spectrum-modulates the voice signal, and wirelessly transmits it. The connection device 5 performs the same operation as in the conventional example, performs spread spectrum demodulation of the received signal, and transmits the voice signal via the wired transmission path 7. The control device 8 also operates in the same manner as in the conventional example, and the control unit 9 is connected to the connection device 5 capable of communicating with another slave device 1 designated at the time of transmitting the slave device in response to the audio signal input from the connection device 5. The output is switched to the wired transmission path 7. Alternatively, if a telephone 11 connected by wire at the time of transmitting the cordless handset is designated, an audio signal is transmitted to the line 1.
Switch to 0 and output. Next, in the connection device 5 to which the audio signal from the control device 8 is input via the wired transmission path 7,
It operates in the same manner as in the conventional example, and spread-spectrum-modulates the voice signal and wirelessly transmits it. The pseudo-noise code storage unit 12 assigns pseudo-noise codes to the designated slave unit 1 in order of good correlation characteristics. The handset 1 to which the pseudo-noise code is assigned operates in the same manner as in the conventional example, and spread-spectrum demodulates the received signal into a voice signal and outputs it to a speaker or the like. Through the above operation, between a plurality of slaves or between the slave 1 and the telephone 1
Voice communication between the two becomes possible.

As described above, according to the present embodiment, the pseudo-noise codes are stored in the pseudo-noise code storage section in the order of good correlation characteristics, and the pseudo-noise codes are assigned to the cordless handset in the order of good correlation characteristics. Therefore, multiplex communication with little mutual interference can be performed.

[0015]

As is apparent from the above embodiments, according to the present invention, since the pseudo-noise code storage section is provided, even in the case where there are many slave units, the correlation characteristics can be improved in the order in which the slave units in communication have good correlation characteristics. It is possible to allocate a pseudo noise code and provide a spread spectrum communication device with less mutual interference between signals.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a spread spectrum communication device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a conventional spread spectrum communication device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Slave unit 3 SS modulation unit 4 SS demodulation unit 5 Connection device 7 Wired transmission line 8 Control device 9 Control unit 12 Pseudo noise code storage unit

Claims (1)

[Claims] 1. A cordless handset for transmitting and receiving a radio signal using a spread spectrum communication system, a connection device capable of wireless communication with the cordless handset, a modulator for performing spread spectrum modulation and demodulation in the cordless handset, and A demodulation unit, a modulation unit and a demodulation unit in the connection device for performing spread spectrum modulation and demodulation, a wire transmission line for transmitting an audio signal, and a control device connected to the wire transmission line,
A pseudo noise code storage unit that stores pseudo noise codes in order of good correlation characteristics; and a control unit that switches the signal input from the demodulation unit in the connection device so as to be output to the modulation unit in the connection device, A spread-spectrum communication device that assigns pseudo-noise codes to slave units in order of good correlation characteristics for multiplex communication.