JPS6360571B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a radio transceiver having a channel designation circuit that sends a channel designation control signal to a frequency synthesizer circuit when a frequency switching signal is input.

Conventionally, in this type of wireless transceiver, power is constantly supplied to the channel designation circuit. but,
This channel designation circuit is required only when switching the frequency, and once the frequency of the frequency synthesizer circuit is locked, it is not necessary until the next time the frequency is switched. If power is constantly supplied to the channel designation circuit as described above, there is a drawback that unnecessary channel designation control signals are sent out from the channel designation circuit, which adversely affects other circuits of the wireless transmitter/receiver. However, there is a drawback that unnecessary current flows through the channel designation circuit.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wireless transceiver that solves the above-mentioned conventional drawbacks, reduces power consumption, and prevents unnecessary channel designation control signals from adversely affecting circuitry.

In order to achieve the above object, a wireless transceiver according to the present invention includes a channel specifying circuit into which a frequency switching signal is input, and a frequency synthesizer circuit whose frequency is locked by a channel specifying control signal sent from the channel specifying circuit. The transmitter/receiver includes a power switch circuit that turns on and off the power of the channel designation circuit, a first detection circuit that detects the frequency switching signal, and a second detection circuit that detects the end of transmission of the channel designation control signal. A detection circuit is provided, and when switching frequencies,
The first detection circuit drives the power switch circuit to turn on the power to the channel designation circuit, and after the end of channel designation, the second detection circuit drives the power supply circuit to It is configured to turn off the power to the channel designation circuit.

According to the configuration of the present invention as described above, when switching the frequency, the power of the channel designation circuit is turned on, channel designation data is sent to the frequency synthesizer circuit, and a strobe signal indicating the end of the data is sent out. , the power of the channel designation circuit can be turned off.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a conventional wireless transmitter/receiver, including a receiving circuit 1, a frequency synthesizer circuit 2, a channel specifying circuit 3, a transmitting circuit 4,
It is composed of an antenna switch 5 and an antenna 6. Next, the operation of a conventional wireless transceiver will be explained with reference to FIG.

First, during reception, a signal coming from the antenna 6 enters the receiving circuit 1 through the antenna switch 5. On the other hand, in the channel designation circuit 3,
As frequency switching signals, a channel switching signal is input from the CH terminal and a transmission/reception switching signal is input from the PRESS terminal. Upon receiving this frequency switching signal, the channel designation circuit 3 sends a channel designation control signal to the frequency synthesizer circuit 2,
Lock the frequency. The output of the frequency synthesizer circuit 2 is input to the receiving circuit 1 as the first local oscillation frequency.

On the other hand, during transmission, by grounding the PRESS terminal, the channel designation control signal sent from the channel designation circuit 3 changes, and the frequency synthesizer circuit 2 is locked to the transmission frequency. The output of the frequency synthesizer circuit enters the transmitter circuit 4 as a second local oscillation frequency, and the signal sent from the transmitter circuit 4 passes through the antenna switch 5 and is radiated from the antenna 6.

Here, power is constantly supplied to the channel designation circuit 3 from the PS terminal. Therefore, as described above, an unnecessary channel designation control signal is sent from the channel designation circuit 3, and an unnecessary current flows into the channel designation circuit 3.

FIG. 2 is a block diagram showing the configuration of an embodiment of the wireless transmitter/receiver according to the present invention. In addition to the circuit shown in FIG. , PRESS and
A first detection circuit 8 that detects a frequency switching signal input from the CH terminal, and a channel designation circuit 3
A second detection circuit is newly provided for detecting a strobe signal that signals the end of channel-designated data sent from the channel. Next, to briefly explain the operation of the circuit shown in Figure 2, PRESS and
The first detection circuit 8 receives a frequency switching signal from the CH terminal, and turns on the power switch circuit 7 when switching the frequency. Thereby, the channel designation circuit 3 sends a channel designation signal to the frequency synthesizer circuit 2. When the sending of the data designated by the channel is completed, the second detection circuit 9 detects this and turns off the power switch circuit.

FIG. 3 is a circuit diagram showing an example of a specific circuit configuration of a part of the wireless transceiver according to the present invention shown in FIG. 2. Hereinafter, the present invention will be explained in more detail using FIG. 3.

Frequency switching signals input from the transmission/reception switching terminal 10 and the channel switching terminal 17 are passed through resistors 11 and 18 and diodes 12 and 19, respectively, and one is directly input to exclusive OR circuits 15 and 22.
On the other hand, resistors 13 and 20 and capacitors 14 and 2
1 integral circuit, exclusive OR circuit 15,
22. Exclusive OR circuit 15, 22
The output of the bistable multivibrator 7a is inputted to the base of one transistor 25 of the bistable multivibrator 7a that constitutes the power switch circuit 7 via the diodes 16, 23 and the resistor 24.
The output of the other transistor 26 is inputted to a switching circuit 7b constituting the other side of the power switch circuit 7, and in this switching circuit 7b, a resistor is passed from the collector of the transistor 32 to the base of the transistor 32 via a resistor 31. It is input to the base of the transistor 34 via 33. On the other hand, among the signals output from the channel designation circuit 3, the strobe signal that indicates the end of channel designation is
The signal is input to the base of the transistor 26 of the bistable multivibrator 7a via a delay circuit including a resistor 40 and a capacitor 37 and a diode 36, which constitute a second detection circuit.

In such a configuration, when the frequency is not switched, the transistor 25 of the bistable multivibrator 7a is off, the transistor 26 is on, and the transistors 32 and 34 of the switching circuit 7b are off, and the channel specifying circuit 3 receives PS. Power is not being supplied from the terminal.

In such a state, when the transmission/reception switching terminal 10 changes from high level to low level, one input of the exclusive OR circuit 15 immediately changes from high level to low level, and the other input changes to the resistor 13 and capacitor 14. It changes from high level to low level with a delay of a time constant determined by
A high level signal appears at the output of the exclusive OR circuit 15 only during a period corresponding to the above time constant. A high level signal outputted from this exclusive OR circuit 15 for a predetermined time is input as a trigger to the base of the transistor 25 of the bistable multivibrator 7a, so that the transistor 25 is turned on and the transistor 26 is turned off to switch. A high-level signal is output to the circuit 7b, and this high-level signal turns on the transistors 32 and 34, and power is supplied to the channel designation circuit 3 from the PS terminal. The channel designation circuit 3 supplied with power in this manner inputs channel designation data to the frequency synthesizer circuit 2. After that, when the channel designation is completed and the strobe signal is output from the channel designation circuit 3, the signal delayed by the time constant determined by the delay circuit including the resistor 40 and the capacitor 37 is used as a trigger to drive the transistor of the bistable multivibrator 7a. 26, the transistor 26 is turned on and a low level signal is output to the switching circuit 7b. This low level signal turns off the transistors 32 and 34, and the power supply to the channel designation circuit 3 is interrupted. It gets cut off.

In addition, in the above explanation, the transmission/reception switching terminal 1
0 changes from high level to low level, but the transmission/reception switching terminal 10
Needless to say, the same operation is performed even when the level changes from low level to high level. Also, it goes without saying that the same operation will occur when the channel switching terminal 17 changes from high level to low level or from low level to high level.

As is clear from the above explanation, according to the present invention, power is supplied to the channel designation circuit only when switching the frequency, which eliminates the negative influence on the circuit due to unnecessary channel designation control signals and reduces power consumption. There is an effect that it can be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a conventional wireless transmitter/receiver, FIG. 2 is a block diagram showing the configuration of an embodiment of the wireless transmitter/receiver according to the present invention, and FIG. 1 is a circuit diagram showing an example of a specific circuit configuration of a part of a wireless transceiver according to the invention; FIG. 1... Receiving circuit, 2... Frequency synthesizer circuit,
3... Channel designation circuit, 4... Transmission circuit, 5... Antenna switch, 6... Antenna, 7... Power switch circuit, 8, 9... Detection circuit.

Claims (1)

[Claims] 1. In a radio transceiver having a channel designation circuit into which a frequency switching signal is input and a frequency synthesizer circuit whose frequency is locked by a channel designation control signal sent from the channel designation circuit, a first
a second detection circuit that detects the end of transmission of the channel designation control signal; and a power supply switching control signal output from the first and second detection circuits to detect the channel designation circuit. A wireless transmitter/receiver characterized by having a power switch circuit that turns on and off power supplied to the wireless transmitter/receiver.