JPH0472832A - Radio repeater - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a repeater (automatic relay station) for wireless communication.

[Conventional technology]

Conventionally, wireless repeater devices have been used to extend the communication range of wireless communication devices with weak output, such as handheld devices, and to enable communication with distant stations.

In this repeater device, for example, in the one shown in FIG. 10, a plurality of antennas 3 are connected at predetermined intervals to a cable 2 extending from a repeater 1 via a branching device 4, and a plurality of antennas 3 are connected to a cable 2 extending from a repeater 1 via a branching device 4, and a slave station a is connected to a cable 2 extending from a repeater 1 at an operating frequency f1. When the transmission is performed, the antenna 3a within the reception area of the slave station a receives it, and transmits it to L. Peter 1 via the cable 2. At this time, for example, when a slave station is transmitting, what is received by the antenna 3b that is far away from the repeater 1 is boosted by the bidirectional booster 5 installed throughout the cable 2 and transmitted to the repeater 1. Ru.

After this signal is received by a receiver fRX provided in the repeater 1, the signal is sent to a transmitter f. Transmission frequency f for transmission again in TX. The signal is modulated and retransmitted to each antenna 3 via the cable 2. At this time, as in the case of reception, the transmission signal is boosted and sent to the distant antenna 3 by the bidirectional booster 5 installed throughout the cable 2. The slave station receives this signal at the receiver f. Receive via RX.

Also, in the case of transmission from the slave station, the transmission frequency fl and reception frequency f are determined by the same operation as described above. It communicates with slave station a using two waves.

In this method, the C due to the friction noise of the booster 5
/NJt (carrier signal-to-noise ratio), the addition of the antenna 3 by adding the booster 5 and the extension of the cable 2 are restricted, and the wireless area cannot be enlarged very much.

On the other hand, as shown in FIG. 9, the repeater 1' is provided with a synthesizer-type transmitter flTX and receiver f2RX,
Furthermore, the transmitter/receiver f, TX, f2R is connected to the repeater.
A reference repeater 1'R equipped with a reference frequency oscillator F for
2RX and sends the demodulated signal to other repeaters 1' including reference repeater 1'R via cable 2,
Each repeater 1'1'R3l'a modulates the signal into a transmission signal using a transmitter f, TX, and transmits it from each antenna 3. In this way, in this method, the transmission signal is not directly sent to the cable 2, but the demodulated signal η sent to the cable 2 is
Transmitter f, T of each terminal repeater 1', 1'a, 1'R
The signal is modulated by X and transmitted from the antenna 3, so that a relatively wide area can be covered without using the booster 5.

Also, at this time, the transmission frequencies of the transmitters f and TX of each repeater 1', 1'a, and 1'R are locked by the reference frequency sent from the reference repeater 1'R. If slave station a is located midway between repeaters 1' and 1'a, due to the difference △r in the transmission frequency between both repeaters 1' and 1'a,
Inter-antenna interference, which causes distortion similar to amplitude modulation to the received signal of slave station a, is prevented.

[Problem to be solved by the invention] However, in the above method, the level of the demodulated signal sent to the cable is low, so noise is easily thrown away. Therefore, as repeaters are installed, the demodulation level decreases. death,
There is still a problem with expanding the wireless area.

Further, conventional repeaters use different transmission frequencies and reception frequencies to prevent transmission signals from going around from the transmitter to the receiver during transmission.

Therefore, two operating frequencies are required: a transmitting frequency and a receiving frequency. For this reason, the transmitter and receiver of the slave stations use different frequencies, so communication between slave stations is not possible outside the Revita area. There are other problems.

Therefore, an object of the present invention is to provide a wireless repeater device 11 that solves the above problems.

[Means to solve the problem]

In order to solve the above problems, in a conventional wireless repeater device, a central repeater having a frequency conversion section consisting of a local oscillation circuit and a mixer circuit is connected to the cable, and a central repeater is connected to the transmitting section of each terminal repeater. A squelch circuit to which a transmission signal is input, a control circuit to which the output of the squelch circuit is input, and an output circuit to control ON10FF by the output of the control circuit are provided. A tuning circuit that is provided with a squelch circuit into which a received signal from the station is input, and an input circuit whose ON/OFF is controlled by the output of the control circuit into which the output of the squelch circuit is input, and which is tuned to the local oscillation frequency. When the terminal repeater receives a transmission signal from a slave station, it converts the signal into an intermediate frequency signal using a local oscillation signal sent from the central repeater and sends it to the central repeater. The signal is reconverted into the transmission signal using the local oscillation frequency and sent to each terminal repeater, and based on this signal, the control circuit determines the transmission/reception status of the terminal repeater, and the terminal repeaters other than the one receiving the signal are The configuration is such that the transmitting state is entered and the transmitting signal is transmitted via the antenna.

Furthermore, the control circuit may be formed using delay circuit elements.

Furthermore, in the wireless repeater device described above, communication with the slave station may be performed using a half-duplex method using a single frequency.

[Effect]

In a wireless repeater device configured in this way, a local oscillation frequency signal is supplied from the central repeater to each terminal repeater via a cable, and when the terminal repeater receives a transmission signal from a slave station, the squelch circuit converts this signal. is detected, the input circuit is turned on by the control circuit, and the transmission signal is converted into an intermediate frequency signal using the local oscillation signal,
It is sent out via a cable to a central repeater. The central repeater reconverts the intermediate frequency signal into the received signal using a local oscillation frequency signal, and retransmits this signal to each terminal repeater via a cable. At this time, when the squelch circuit detects this signal in the terminal repeater other than the receiving terminal, the control circuit turns off the input circuit and turns on the output circuit to enter the transmitting state, and the signal is transmitted via the antenna. Ru. On the other hand, in the terminal repeater during reception, the control circuit maintains a reception state in which the input circuit is ONL and the output circuit is OFF. Further, when the transmission signal from the slave station stops and this is detected by the squelch circuit, the input/output circuit of each terminal repeater is put into a standby state by the control circuit with the input/output circuit set to 0FFL.

Furthermore, if the control circuit is formed using delay circuit elements, the control signal of the control circuit can be generated from the output of the squelch circuit.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 8.

The wireless repeater device shown in the block diagram of FIG. Bidirectional boosters 5 are provided at required intervals.

This wireless repeater device frequency-converts the transmission signal (hereinafter referred to as RF multiplied signal) from the slave station 1m received by the terminal repeater 1T to an intermediate frequency signal (hereinafter referred to as IF multiplied signal), a frequency sufficiently lower than that of the so-called carrier wave. , sent to central repeater 1C via cable 2, central repeater 1C
Now, the same RF that this IF multiplied signal slave station 1m transmitted.
Reconvert the signal and send it to terminal repeater 1 via cable 2.
T...nT, and is transmitted from the antenna 3 of the terminal repeater 2T...nT other than the terminal repeater 1T which is receiving the RF multiplied signal from the slave station 1m.
For this reason, the central repeater 1C is provided with a frequency conversion section.

The frequency converter t includes a mixing circuit (hereinafter referred to as MIX) 1
0 and a local oscillation circuit (hereinafter referred to as LO) 11, MIXIO is connected to a terminal repeater 1T via an input circuit 12.
Station transmission from IF double signal LOll sent from −υ
r1. The RFF signal obtained from the sideband by the filter circuit (tuning circuit) fA is sent to the cable 2 via the duplexer DF. In addition, L Ol 1 is directly connected to cable 2 via duplexer DF, and local oscillator signal fL is sent to each terminal repeater 1T...nT.
Send out. The frequency of this local oscillation signal fL is a multiple of that frequency or a divided frequency, etc.
When the F signal and the IFF signal are superimposed, a frequency is selected that does not easily affect the signal.

The terminal repeater 1T consists of a receiving section R, a transmitting section T, and a control circuit C80, and the receiving section R is provided with a tuning circuit (filter) fll.
The local oscillator signal f t is selected and received from F, RF, and the local oscillator signal fL. In addition, if this local oscillation signal ft is multiplied by a factor of 1, it is frequency-divided by a multiplier frequency dividing circuit 13,
On the other hand, if the frequency is divided, the frequency divider circuit 1
3, the original local oscillation signal rL is multiplied by
Input to IXIO'.

Furthermore, the reception section R is provided with a squelch circuit 14 connected to the input end of the input circuit 17, which detects the input signal level received from the antenna 3 by the tuning circuit f (le), and detects the level of the input signal received from the antenna 3 by the tuning circuit f (le). When it detects the transmission signal, it outputs an ON output as shown in FIG. 2A.

The output of the input circuit 17 is connected to the MTXIQ', and MIXIO' receives the RF signal received from the slave station 1m.
The F signal is mixed with the local oscillation signal rL to generate an intermediate frequency signal, and the lower side wave portion of the sideband is sent to the cable 2 by the filter flF.

On the other hand, the transmitter Tr is provided with a tuning circuit (filter) fe as described above, and from among the local oscillation signal fL, RF signal, and TFF signal mixed on the cable 2, the central repeater 1
The RFF signal reconverted by C is selectively received. The output circuit 16 is connected to this output, and the input terminal thereof is
A squelch circuit 15 is connected to the squelch circuit 15.
outputs an ON10FF signal as shown in FIG. 2B depending on the RFF signal level from the central repeater 1C.

The outputs A and B of both squelch circuits 14 and 15 are input to a control circuit C87, and for example, the circuit shown in FIG.
It operates according to the time chart shown in the figure, and turns on the input circuit 17 and the output circuit 16 to prevent input signals from entering the input circuit 17 during transmission or by reflected waves due to impedance mismatching with the antenna 3. This prevents the output circuits 16 and 17 from malfunctioning and enables semi-duplex communication using a single frequency. Furthermore, as mentioned above, since this repeater device does not directly send demodulated signals such as audio signals to the central repeater 1C as in the conventional case,
The influence of induced lightning surges on outgoing signals and the influence of noise on other signal systems can be minimized.

Furthermore, since modulation and demodulation are not performed at that time, the data
It is applicable to both voice and communication.

This embodiment is constructed as described above, and the local oscillator signal fL is sent from the central repeater 1C via the cable 2 to each terminal repeater 1T...nT, and each terminal repeater 1T... ... nT is in standby state.

Now, transmission is performed from the slave station 1m, and the terminal repeater 1T whose reception area is the transmission location of the slave station 1m is a tuned circuit f.

This signal is received by the squelch circuit 14, and the level is determined by the squelch circuit 14, and the ONN signal is sent to the furnace control circuit C6.
When the signal is output to 0, the control circuit C0, causes the flip-flop (hereinafter referred to as FF) a to delay this signal, A, and 17 to delay the output of the squelch circuit 15, BI.
The ll and Y signals are read, and if the FFa output is 'I]', the output turns on the input circuit 17 to put the terminal repeater 1T in the receiving state, and inputs it to the RFF signal MTX10'. On the other hand, when the FFa output becomes L', the terminal repeater 1T is in a transmitting state, so the input circuit 17 remains OFF.

This MTXIO' has a filter circuit f from cable 2.
The local oscillator signal fL obtained by ll is added,
The RFF signal is mixed, and the I
The FF signal is taken out and sent to the cable 2 via the duplexer DF. At this time, since the transmission level of this signal can be sufficiently lowered, the signal level can be made higher than the heating noise of the booster 5 provided on the cable 2. Therefore, the C/N ratio can be improved, and the length of the cable 2 can be made longer than the conventional one.
Therefore, the wireless area can also be widened.

The IF multiplied signal sent to the cable 2 is received by the central repeater 1C, inputted to the MIXlo via the input circuit 12, and mixed with the local oscillation signal f. At this time, since the local oscillator signal ft is the same as that supplied to the terminal repeater 1T...nT, its sideband is used to generate the same RF signal as the transmission signal of the slave station 1m. The signal is reconverted and retransmitted via cable 2 to terminal repeater 1T...nT.

This RF multiplied signal is received by the tuning circuit rc of each terminal repeater 1T...nT, the output level is determined by the squelch circuit 15, and the ON output B is inputted to the control circuit C6ゎ, and the control circuit C80 A D that delays the output of the squelch circuit 14 in FFb with its output.
1. When the Y signal is read and the output is 'H', the output circuit 16 is turned on and transmission is started. At this time, the squelch circuit 14 detects the RF multiplied signal, and based on its output, FFa of the control circuit C0° becomes B. In order to read the L signal and turn off the input circuit 17 with its output, the R
The loopback to the F-fold signal input circuit 17 is prevented.

On the other hand, terminal repeater 1T receiving transmission from slave station 1m
Then, as shown in FIG. 2 (■), the A D +,'/ signal is read into FFb by the B DLV, and the 'I,' output is output, so the output circuit 16 continues to be in the OFF state. Reception status is maintained.

Next, the slave station 1m enters the receiving state, and the RF from the slave station 1m
When the double signal disappears, squelch circuit 1 of terminal repeater 1T
7 outputs an OFF output to the control wholesale circuit C0°, FFa is reset and its output becomes L", so the input circuit 17 is turned OFF and no longer outputs the IF multiplied signal sent to the central repeater 1T. , the RF multiplied signal from the central repeater 1C is no longer output, and each terminal repeater 1T
. . . The squelch circuit 15 of nT outputs an OFF output to the control circuit C°7. As a result, FFb is also reset, and the output circuit 16 is set to 0FFL, and each terminal repeater 1T.
... nT enters standby state. Thereafter, when there is a transmission from another slave station, for example 2m, the terminal repeater 2T within the reception area enters the reception state, repeats the above operation, and performs half-duplex communication using a single frequency. For this reason,
Slave station 1m...The nm is a 1m slave station that uses a half-duplex system in which the transmitter and receiver of the same frequency are switched by a switch.
....nm is used, so the slave station is 1m...
Transmission and reception between nanometers can also be performed. Therefore, the cost of the slave station 1 is reduced, and frequencies can be used more effectively.

Furthermore, in this repeater device, the transmitting and receiving frequencies can be easily changed by simply changing the local oscillation frequency ft of the central repeater 1C.

As shown in Fig. 4, the squelch circuit 14 of the terminal repeater 1T...nT can operate at two levels: 14', which operates at a weak level, and 14'', which operates at a strong level. By doing so, sending and receiving OF
Create the F mode, control the input/output circuits 17 and 16 according to the time chart shown in Figure 5, determine the operation of the terminal repeater as shown in Figure 6, and prevent phase difference interference between the antennas 3. It can be assumed that A specific example of the control circuit C87' used at this time is shown in FIG.

Furthermore, by using different tuning frequencies for the tuning circuits of the repeaters 1C11T...nT, and performing frequency division, as shown in Figure 8, the cable can be shared to support multiple wireless systems. You can also do that.

〔effect〕

Since the present invention is configured as described above, it is effective in expanding the wireless area for mobile communication.

That is, this repeater device exhibits the following effects.

(2) Since no modulation/demodulation is performed, it can be applied to both data and voice communications.

2) Two independent wireless systems and a coaxial trunk line can be shared.

3) Effective use of frequencies is possible because communication is performed using a single frequency, half-duplex.

4) Since the transmitted signal from the slave station is converted into an IF signal by the terminal repeater and at the same time raises its level, the signal level can be made higher than the sink noise of the sink. This makes it possible to extend the cable and further expand the wireless expansion area.

5) Since the audio demodulated signal is not sent to the repeater via cable as in the past, the influence of induced lightning surges on the outgoing signal and the influence of noise on other signal systems can be minimized.

6) The slave stations used in this wireless repeater device can communicate with each other within a range of about 100 meters even without a repeater.

[Brief explanation of the drawing]

1 to 8 show an embodiment of the wireless repeater device according to the present invention, FIG. 1 is a block diagram, FIG. 2 is an operational diagram, FIG. 3 is a circuit diagram of a control circuit, and FIG. 4 is a terminal. A block diagram of another embodiment of the repeater device, FIGS. 5 and 6 are operational diagrams of FIG. 4, FIG. 7 is a control circuit of another embodiment, and FIG. 8 is an operational diagram of another embodiment. FIGS. 9 and 10 are block diagrams of conventional examples. 1C...Central repeater, 1T...nT...Terminal repeater, 1m
... nm ... slave station, 2 ... cable, 3 ... antenna, 11 ...
...Local oscillation circuit, 10.10'...Mixer circuit, L...Frequency conversion section, T,...
...Transmission unit, 14...Squelch circuit, c
o□... Control circuit, 16... Output circuit, R... Receiving section, 15... Squelch circuit. Patent applicant Sumitomo Electric Industries Co., Ltd. Agent Fumi Kamata

Claims (3)

[Claims] (1) A plurality of terminal repeaters each having a transmitting/receiving section are connected to each other via a cable, and when one of the terminal repeaters receives a transmission signal from a slave station, this signal is sent to the other repeaters via the cable. sending out, other repeaters,
In a wireless repeater device that transmits the signal via an antenna, a central repeater having a frequency conversion section consisting of a local oscillation circuit and a mixer circuit is connected to the cable, and
A squelch circuit into which a transmission signal from the central repeater is input to the transmission section of each terminal repeater, a control circuit into which the output of the squelch circuit is input, and an output circuit whose ON/OFF is controlled by the output of the control circuit. established,
The reception section is provided with a squelch circuit into which the received signal from the slave station is input, and an input circuit whose ON/OFF is controlled by the output of the control circuit into which the output of the squelch circuit is input, and the local oscillation. A tuning circuit that tunes to the frequency is provided, and when the terminal repeater receives a transmission signal from a slave station, it converts the signal into an intermediate frequency signal using a local oscillation signal sent from the central repeater, and sends it to the central repeater. , the central repeater reconverts this signal into the transmission signal using the local oscillation frequency and sends it to each terminal repeater. Based on this signal, the control circuit determines the transmission/reception status of the terminal repeater, and A wireless repeater device characterized in that the terminal repeater enters a transmitting state and transmits the transmission signal via an antenna. (2) The wireless repeater device according to claim 1, wherein the control circuit is formed using a delay circuit element. (3) The wireless repeater device according to claims (1) and (2), characterized in that it communicates with the slave station by a half-duplex method using a single frequency.