JPH04267643A - Transmitter-receiver - Google Patents

Abstract

PURPOSE:To implement rough adjustment of a receiver and an operation check without use of an external measurement device with respect to the simplex system transmitter-receiver. CONSTITUTION:The transmitter-receiver is provided with a transmitter 3 receiving a DC voltage from a transmission power supply section 1 to be brought into operation with a press switch section 6 turned on and sending a transmission signal via an antenna changeover device 5 and with a receiver 4 brought into operation with the application of a DC power supply from a reception power supply 2 and receiving a signal inputted via the antenna changeover device, and a test switch SW to apply the DC voltage to the transmitter from the transmission power supply section with the press switch section turned off, In the case of testing the receiver, the receiver is brought into the operation and the test switch is closed to allow the transmission signal from the transmitter in the operating state to pass through the antenna changeover device thrown to the position of the sender side and to be fed to the receiver.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simplex transmitter/receiver. The recent development of mobile communications is remarkable, and the target mobile devices are not limited to automobiles, trains, ships, and aircraft, but are also expanding to include personal use.

[0002] In the simplex system, there are cases in which transmission and reception are performed using the same frequency and cases where transmission and reception are performed using different frequencies, and the simplex system to which the present invention is directed is the former case.

[0003] Now, in order to speed up the service and reduce costs for mobile communications, which are developing in this way, it is possible to make rough adjustments and check the operation of the receiver without using external measuring equipment. It is necessary.

0004

2. Description of the Related Art FIG. 3 shows a block diagram of a conventional example, and the operation of the diagram will be explained. (1) Receiver operation First, there is a transmitting power supply section 1 and a receiving power supply section 2, each having a primary voltage input terminal, a secondary voltage output terminal, and a control terminal (not shown). It is assumed that the configuration is such that a secondary voltage is output by being grounded.

Now, when the press switch 61 is in the OFF state, a primary DC voltage of, for example, +14V is applied to the reception power supply section 2. As a result, from this power supply part,
For example, a DC voltage of +8V is applied and the receiver is in operation.

Now, for example, when a 150 MHz band radio wave is input to the antenna switching device 5 via an antenna, the antenna switching device 5 is in a solid line state, so that it is applied to the high frequency band pass filter BPF1.

The high frequency band pass filter BPF1 removes unnecessary wave components from the incoming radio wave, that is, the received signal, and then sends it to the high frequency amplifier 41. Therefore, this amplifier 41 amplifies the signal by a predetermined amount and sends it to the high frequency band pass filter BPF2.

The high frequency band pass filter BPF2 extracts only the desired wave and applies it to the first frequency mixer 43. On the other hand, since the first local oscillator signal from the first local oscillator 42 is also added here, the two signals are mixed and 150M
The signal in the Hz band is the first intermediate frequency band (for example, 10.7M
Hz band) signal.

However, since the signal in the first intermediate frequency band also contains unnecessary waves generated by the above-mentioned mixing, after removing the unnecessary waves with the first intermediate frequency band pass filter BPF3,
The signal is again amplified by the first intermediate frequency band amplifier 44 and applied to the second frequency converter 46 .

Here, the second local oscillator 45 outputs the second
Since the local oscillator signal is also added, it is converted to a signal in the second intermediate frequency band (for example, 455 KHz band). This second
The intermediate frequency band signal is passed through a second intermediate frequency bandpass filter BP.
After removing unnecessary waves with F4, the second intermediate frequency band amplifier 47
The signal is amplified and applied to the demodulator 48.

The demodulator 48 demodulates the input signal to extract, for example, an audio signal, and drives the speaker SP via the audio signal amplifier 49, so that the corresponding audio is transmitted. (2) Transmitter operation Next, press the press switch 61 to turn it on.
Since the control terminal of the transmitting power supply part 1 is grounded, the transmitting power supply part 1 operates and +8V DC voltage is applied to the transmitter, and the control terminal of the receiving power supply part 2 becomes open, and the DC voltage is applied to the transmitter. There will be no output and no DC voltage will be applied to the receiver.

[0012] As a result, the receiver becomes inactive, the transmitter becomes active, and the antenna switch 5 is switched to the transmitting side as indicated by the dotted line. Now, the audio signal from the microphone MIC is amplified by the audio signal amplifier 31 and applied to the modulator 32. The modulator modulates the carrier with the audio signal to generate a modulated wave with the same frequency as the reception frequency.

[0013] Then, the signal is amplified to a predetermined power by a power amplifier 33 and transmitted via an antenna switch. Here, the receiver of the transmitting/receiving device includes a high frequency band pass filter, a first intermediate frequency band pass filter, a second intermediate frequency band pass filter, an audio signal amplifier, etc. as described above. Usually has an adjustment section consisting of variable capacitance, variable inductance, variable resistor, etc.

[0014] These adjustments are normally made by applying a signal of the same frequency as the receiving frequency from a standard signal generator to the receiver. In other words, the standard signal generator is indispensable for adjusting the receiver, and it can be used at the rough adjustment stage of the transmitter/receiver, or when it becomes necessary to change the reception frequency for some reason after shipment from the factory, or in the event of a breakdown or repair. This generator is widely used during readjustment.

[0015]

[Problem to be solved by the invention] As mentioned above, standard signal generators are indispensable for adjusting receivers during inspection and readjustment during production process stages and failure repairs, so the number of standard signal generators used is As the number of requests increases, there are cases where prompt service cannot be provided.

[0016] Therefore, there is a problem in that it is necessary to be able to make rough adjustments and check the operation of the receiver without using an external measuring device. An object of the present invention is to enable rough adjustment and operation check of a receiver without using external measuring equipment.

[0017]

[Means for Solving the Problems] FIG. 1 is a block diagram of the principle of the present invention. In the figure, when the press switch part 3 is turned on, DC voltage is applied from the transmitting power supply part, and it becomes operational, and a transmitting signal of frequency f is sent out through the antenna switcher switched to the transmitting side. It is a transmitter.

Further, when the press switch part is in the off state, the DC voltage from the receiving power supply part is applied to the press switch part 4, and the frequency f is inputted through the antenna switcher which is switched to the receiving side. It is a receiver that receives the signal.

Further, SW is a test switch for outputting a DC voltage from the transmission power source section and applying it to the transmitter when the press switch is in the off state. When testing the receiver, the receiver is put into operation, the test switch is turned on, and the transmission signal from the transmitter, which is now in operation, is transferred to the antenna which has been switched to the transmitting side. The configuration was such that the switch was leaked and added to the receiver.

[0020]

[Operation] According to the present invention, a test switch SW is provided on, for example, a printed circuit board, and this switch is inserted between a control terminal of a transmitter power supply section and ground.

[0021]The configuration was such that both the transmitter and the receiver operated by turning on the test switch. Also, the antenna switch gives priority to transmission operations. That is, when adjusting the receiver, first, the receiver is put into a receiving state, and then the test switch is turned on to apply the DC voltage applied to the receiver to the transmitter, thereby operating the transmitter.

[0022] As a result, the antenna switch is switched to the transmitting side, so that the transmission signal from the transmitter is sent to the antenna. However, the transmitted signal is a high frequency (e.g. 150MH
Z band), it propagates through the space inside the antenna switch and appears attenuated to some extent on the receiving side. At this time, the transmitting frequency and the receiving frequency are the same, so the receiver receives normally.

[0023] Using this signal, it is possible to make rough adjustments to filters etc. provided in the receiver and to perform simple checks on the receiver.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 2 shows a block diagram of an embodiment of the invention. Note that the same reference numerals indicate the same objects throughout the figures. Further, the part of the present invention is the part of the test switch SW.

The operation shown in the figure will be explained below, but since the operation of the receiver and transmitter alone has been explained in detail above, the explanation of the operation will be omitted, and only the parts of the present invention will be explained in detail. In the figure, when the press switch 61 is in the OFF state, a primary DC voltage of, for example, +14V is applied to the receiving power supply section 2. Note that the transmission power supply section 1 is in a non-operating state.

Therefore, for example, +8
Since a DC voltage of V is applied to the receiver 4, the receiver becomes operational, and the antenna switch 5 switches to the receiving side as shown by the solid line.

When the test switch SW is turned on in this state, a DC voltage of +8V is applied from the transmission power supply section 1 to the transmitter 3. Then, when the transmitter 3 becomes operational, the antenna switch 5 switches to the transmitting side as shown by the dotted line, so that the transmission signal from the transmitter is sent out to the antenna through the antenna switch.

However, a part of the signal leaks through the antenna switching device and appears at the high frequency band pass filter BPF1 of the receiver, but at this time the receiver is in a state of receiving the signal. In this state, while detecting the reception level of the intermediate frequency stage of the receiver, rough adjustment of the adjustment section within the receiver and operation check of the receiving section are performed.

When the adjustment and testing inside the receiver is completed, the switch SW is turned off to return to the normal reception state. Then, when the press switch is turned on, the transmitter becomes active and the receiver becomes inactive.

That is, it is possible to make rough adjustments and check the operation of the receiver without using an external measuring device.

[0031]

As described in detail above, according to the present invention, there is an effect that rough adjustment and operation check of the receiver can be performed without using an external measuring device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the principle of the present invention.

FIG. 2 is a block diagram of an embodiment.

FIG. 3 is a block diagram of a conventional example.

[Explanation of symbols]

1 Transmission power supply part 2　Receiver power supply part 3 Transmitter 4 Receiver 5　Antenna switcher 6 Press switch SW Test switch

Claims (1)

[Claims] [Claim 1] When the press switch part (6) is turned on, DC voltage from the transmitting power supply part (1) is applied to the transmitting power supply part (1), and the antenna is switched to the transmitting side via the antenna switch (5). When the transmitter (3), which sends out a transmission signal of frequency f, and the press switch part are in the off state, DC voltage from the reception power supply part (2) is applied to the transmitter (3), which turns it into an operating state and switches to the receiving side. and a receiver (4) for receiving a signal of frequency f inputted via the antenna switch, in which a DC voltage is output from the transmitting power supply section when the press switch section is in an OFF state. Test switch (SW) for adding to the transmitter
), and when testing the receiver, the receiver is put into the operating state, the test switch is turned on, and the transmitted signal from the transmitter that is in the operating state is switched to the transmitting side. A transmitting/receiving device characterized in that the antenna switching device is configured to be leaked and added to a receiver.