JPS5922421B2 - wireless communication device - Google Patents

Description

[Detailed Description of the Invention] The present invention enables the power to be turned on and off at regular intervals during standby reception.
This invention relates to a wireless communication device having a power saving function for continuously supplying FF to required circuits, and in particular, it further improves the power saving effect of the wireless communication device by shortening the squelch response time of the squelch circuit.

The operating states of a wireless communication device include a transmitting state, a receiving state, and a standby receiving state.In particular, in the standby receiving state, the power is turned on and off at regular intervals, and the power supply (battery) is used to supply the necessary circuits. Longer lifespan (power saving effect)
This is preferable in this respect.

Here, a block diagram of a receiver of a wireless communication device having a power saving function is shown in FIG. In FIG. 1, high-frequency human power from an antenna 1 is amplified by a high-frequency amplifying section 2, and a mixing section 3
is mixed with the oscillation output from the local oscillator 4, amplified as an intermediate frequency signal by the intermediate frequency amplifier 5, detected by the detector 6, amplified by the low frequency amplifier T, and output to the speaker 8.
It will be played at. A squelch unit 9 connected in parallel between the detection unit 6 and the low frequency amplification unit 7 suppresses the audio line or power line of the low frequency amplification unit 7 based on the noise output of the detection unit 6. In such a configuration, the power supply section 10 is directly connected to the low frequency amplification section 7, the squelch section 9, the oscillation section 11 such as a multivibrator, and the switching section 12, so that the power supply +B is continuously supplied. . On the other hand, the switching section 12 outputs the oscillation output of the oscillation section 11 to the high frequency amplification section 2, mixing section 3, local oscillation fertilizer 4, intermediate frequency amplification section 5, and detection section 6 connected to the power supply section 10 via the switching section 12. Since VON-OFF is performed according to this cycle, power +B is continuously supplied based on this cycle. In such a wireless communication device with a power-saving function, in order to increase the power-saving effect, it is sufficient to increase the cycle of ON and OFF times of the power supplied to the required circuits 2, 3, 4, 5, and 6. For example, in the United States, the receiver rise time is 150
ms, and cannot be made too large.

On the other hand, it is possible to increase the ratio of the power ON time to the power OFF time, but in this case, there are two methods: a method of increasing the OFF time and a method of shortening the ON time. A method of increasing the OFF time is not very preferable in terms of the reception frequency. Furthermore, since the presence or absence of a received signal is determined based on the output of the squelch section 9 and the low frequency amplification section 7 and the oscillation section 11 are controlled, the power ON time cannot be made very short due to the squelch response time. Next, the configuration of the squelch section 9 is shown in FIG.

The input terminal P1 reaches the detection section 6, and the output terminal P2 reaches the interrogation wave amplification section 7 and the oscillation section 11. The noise from the detection section 6 is converted into an F wave by a noise filter 91, amplified by a noise amplifier 92, and then passed through a capacitor Cl and a diode D.
1 and D2 to double the voltage and charge the noise smoothing capacitor C2. With this voltage, the squelch control transistor Q1 performs 0N/0FF operation. Here, the squelch response time can be shortened by reducing the capacitance of the capacitor C2, but since the pulse noise resistance characteristics will deteriorate, the capacitance cannot be reduced either. Referring to FIG. 3, (a) shows one cycle of power ON-OFF, and (b)
indicates the output change of output terminal P2, and the time required for squelch after power is applied when no signal is applied is t1.
Then, the power applied to the required circuits 2, 34, 5 and 6 must last for a time T2, which is longer than the time t1. However, if the time T2 is long, the power ON-O
One period T of F switching cannot be taken very long due to the rise time of the receiver, and is divided into 0N time T2 and 0FF time T3.
ratio becomes small, and the expected power saving effect cannot be expected. This time t1 changes depending on the setting value of the variable volume VR for squelch adjustment, but in the case of squelch tight, it is 10
About mS, 40 for squelch threshold hold
It is about mS. Therefore, it can be seen that the ON time T2 during power switching cannot be shorter than the squelch closing time. In order to improve this problem, the present invention generates a short pulse when the power is turned on during the power saving period of power ON and OFF, and applies this pulse to the noise smoothing capacitor. It is expected that the power saving effect will be improved by charging the battery in a timely manner, further shortening the squelch response time, and shortening the power ON time.

Hereinafter, one embodiment of the present invention will be described based on FIGS. 4 and 5.

FIG. 4 shows an improved squelch circuit 9 and its peripheral circuits according to the present invention. In FIG. 4, the same parts as in FIG. 3 are given the same reference numerals. Particularly improved parts are 93, a pulse generating means. The input side of the pulse generating means 93 is connected to the output side of the switching section 12, and the output side is connected to the noise smoothing capacitor C2.
According to such a configuration, with reference to FIG.
c shows the output change of output terminal P2,
When the power supply becomes ON, the pulse generating means 93 generates a short pulse.

This output pulse is applied to the noise smoothing capacitor C2 and forcibly charges the capacitor C2 quickly, so the time tl required for squelch to occur when there is no signal is approximately 0.7 to 0.8 mS, according to experimental values. becomes very short. A monostable multivibrator can be considered as the pulse generating means 93, but a single capacitor can also perform the same function. Comparing one embodiment of the present invention and a conventional example, the time required for squelch to occur when there is no signal is t.
1《tl, so the power ON time can be set to T2 × T2, and even when the power saving period T=T, according to the present invention, the ratio of the power ON time T2 to the power OFF time T3 can be made large. It can be seen that more power saving effects can be expected. Further, according to the present invention, there is no need to reduce the capacitance of the noise smoothing capacitor, so the pulse noise resistance characteristics are not impaired.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a wireless communication device with a power saving function, Figure 2 is a diagram showing an example of the squelch section of a wireless communication device, and Figure 3
2 is a waveform diagram of a required part in FIG. 2, FIG. 4 is a diagram of an embodiment of the squelch section of a wireless communication device according to the present invention, and FIG. 5 is a waveform diagram of a required part in FIG. 4. In the figure, 2 is a high frequency amplification section, 3 is a mixing section, 4 is a local oscillation section, 5 is an intermediate frequency amplification section, 6 is a detection section, 7 is a low frequency amplification section, 9 is a squelch section, 10 is a power supply section 11 is 12 is a switching section, 9 is a noise filter, 92 is a noise amplifier, and 93 is a pulse generating means.

Claims (1)

[Claims] 1 An antenna, a high frequency amplification section, a mixing section, a local oscillation section, an intermediate frequency amplification section, a detection section, a low frequency amplification section,
In a wireless communication device that consists of a speaker and a squelch section, and is designed to continuously supply power to the necessary sections during standby reception by turning on and off, the noise smoothing capacitor provided in the squelch section is forced to close when the power is turned on. A wireless communication device having a pulse generating means for charging.