JPH0821874B2 - Wireless communication equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a wireless communication device that reduces the current consumption of a receiving unit in various wireless devices including a high frequency amplifier.

SUMMARY OF THE INVENTION The present invention provides a wireless device including a receiving unit and a control unit,
When the reception signal level at the time of reception is detected by the envelope detector and is a sufficient reception level that does not require the amplification degree of the radio frequency amplifier of the radio device, the radio frequency amplifier is bypassed without supplying power to the radio frequency amplifier. By providing a high-frequency signal bypass path, the current consumption of the wireless device can be reduced.

[Prior Art] Conventionally, as a method of controlling the amplification degree of a radio frequency receiver high frequency amplifier, a forward AGC amplifier circuit or a backward AGC amplifier is used.
An amplifier circuit or the like is used to adopt a control method in which the output signal level of the high frequency amplifier is always constant even if the received signal level changes, and the high frequency amplifier itself is bypassed. There wasn't.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional technique, when the reception signal level when the radio is in the reception state is a sufficient reception signal level that does not require the amplification degree of the high frequency amplifier of the radio. However, the high-frequency amplifier operates and consumes unnecessary power, which is an obstacle to the reduction in power consumption of the wireless device.

Further, in the above-mentioned conventional technique, when a forward AGC circuit is used, at a sufficient reception signal level that does not require the amplification degree of the radio frequency amplifier of the radio device, more current consumption than at the time of normal operation is performed. It becomes an adverse effect of lowering the power consumption of the wireless device, and when using the reverse AGC amplifier circuit, when the received signal level is sufficient that does not require the amplification degree of the high frequency amplifier of the wireless device, normal operation There is a problem that the current consumption may be slightly smaller than that of the case, or non-linear distortion is likely to occur and the intermodulation characteristics are deteriorated.

[Means for Solving the Problems] In order to solve the above problems, in the present invention, a level detecting means for detecting a signal level of a received signal is provided in a radio device including a receiving section and a control section, and a high frequency amplifying section. A high frequency amplifier for amplifying the received signal, a signal bypass path for bypassing the high frequency amplifier for the received signal, and a signal path switching means for switching the path of the received signal between the high frequency amplifier and the signal bypass path are provided. Further, the power supply to the high frequency amplification unit can be controlled independently of the power supply to the reception unit.

[Operation] According to the above configuration, when the wireless device is in the receiving state, the control unit can constantly monitor the received signal level by using the level detection means, and the amplification degree of the high frequency amplifier is required. If the reception level is not sufficient, the signal bypass path that bypasses the high-frequency amplifier is selected to reduce the power consumption of the wireless device. Further, by supplying / stopping the power to the high frequency amplifier, the signal path of the received signal can be selected to one of the high frequency amplifier and the signal bypass path, and the power is stopped when the signal bypass path is selected, resulting in low power consumption. Can be measured.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a main part of a wireless communication device according to the present invention.

In the figure, 1 is an antenna, 2 is a receiving section, 3 is signal path switchers 4a and 4b as signal switching means, a high frequency amplifier 5, and a bypass path 6 as a signal bypass path.
A high-frequency amplifier having, a 7 is an envelope detector as a level detecting means composed of a logarithmic amplifier 8 and an envelope detector 9, 10 is a comparator, 11 is a reference voltage device, 12 is a control unit, 13 is a power supply. Reference numeral 14 is a power switch.

Next, the operation will be described. The signal A received by the antenna 1 is input to the high frequency amplifier 3 of the receiver 2.
Normally, the power supply control signal G of the control unit 12 is generated by the power switch 14.
Since the control is such that it is turned on, the signal path switches 4a and 4b of the high frequency amplifier 3 are connected to the high frequency amplifier 5 side. At this time, the high frequency amplifier output signal B is a signal obtained by amplifying the signal A received by the antenna 1 by the amplification degree of the high frequency amplifier 5.

Here, the operation when the signal A received by the antenna 1 is at a high level will be shown. The intermediate frequency signal C of the receiver 3 is level-compressed by the logarithmic amplifier 8 in the envelope detector 7, envelope-detected by the envelope detector 9, and the envelope detection output D
Is input to the comparator 10. The comparator 10 compares the envelope detection output D of the envelope detector 7 and a preset reference voltage signal E of the reference voltage device 11 to obtain a comparison determination signal F.
Is output to the control unit 12. Based on this comparison / determination signal F, the control unit 12 causes the signal A received by the antenna 1 to be the high frequency amplifier 5
It is judged that the voltage control signal G is turned off by deciding that it is at a sufficient level that does not require the amplification degree. As a result, the power switch 14 is opened and the high frequency amplification unit power supply I is not supplied to the high frequency amplification unit 3. When the high frequency amplification unit power I is no longer supplied to the high frequency amplification unit 3, the signal path switches 4a and 4b are connected to the bypass path 6 side, and the signal A received by the antenna 1 becomes the high frequency amplification unit output signal B as it is.

With such a configuration, the effect is that the signal A received by the antenna 1 when the wireless unit is in the receiving state is at a sufficient level that does not require the amplification degree of the high frequency amplifier 5 in the high frequency amplification unit 3. For example, it is possible to stop the supply of the power supply I of the high frequency amplification unit and reduce the power consumption of the wireless device.

Next, an embodiment of the high frequency amplifier of the present invention will be described with reference to the drawings.

In FIG. 2, the operation when the high frequency amplifier power S3 is supplied will be described. The high frequency amplifier power supply S3 is supplied to the PIN diode D1 and the PIN diode D2 via the high frequency amplifier A1 and the choke coil L1, and the PIN diode D1 and the PIN diode D2 are forward biased, and the PIN diode D1 and the PIN diode D2 are supplied. The characteristics of themselves are short-circuited, and the impedance at point P is almost 0Ω. Here, the first microstrip line B1 and the second microstrip line B2 each have a characteristic impedance of Z0 and an electrical length of microstrip that is 1/2 wavelength of fc when the frequency of the input signal S1 is fc. Since it is composed of a line, the impedance seen from the point M to the first microstrip line B1 side is infinite, and the circuit on the side of the first microstrip line B1 with respect to the point M is
It operates as if nothing is connected, the impedance seen from the N point to the second microstrip line B2 side is infinite, and the circuit on the second microstrip line B2 side with respect to the N point is as if Works as if nothing was connected. Therefore, the input signal S1 is the PIN diode D
It is amplified by the high frequency amplifier A1 through 1 and becomes the output signal S2.

Next, the operation when the high frequency amplifier power S3 is not supplied will be described. Since the PIN diode D1 and the PIN diode D2 are not biased, they are turned off and have high impedance. Therefore, the input signal S1 becomes the output signal S2 from the point M through the first microstrip line B1, the second microstrip line B2, and the point N with almost no attenuation.

[Advantages of the Invention] As described above, the radio communication device does not have a feedback circuit in the high-frequency amplification unit to control the amplification degree of the high-frequency amplification unit, and directly turns on / off the power of the high-frequency amplification unit. Therefore, there is an advantage that a stable operation can be realized and the present invention can be applied to a high frequency amplifier having no input terminal for amplification degree control.

[Brief description of drawings]

FIG. 1 is a block diagram showing a main part of an embodiment of a wireless communication device according to the present invention, and FIG. 2 is a circuit diagram showing an embodiment of a high frequency amplifier used in the wireless communication device according to the present invention. 2 ... Receiver 3 ... High frequency amplifier 5 ... High frequency amplifier 6 ... Bypass path 7 ... Envelope detector 8 ... Logarithmic amplifier 9 ... Envelope detector 10 ... Comparator 12 ... Control unit A: Received signal B: High frequency amplifier output signal

Claims (2)

[Claims] 1. A wireless communication device comprising: a receiver having an antenna for receiving a signal of a desired frequency; a power supply for supplying power to the receiver; and a controller for controlling power supply from at least the power supply. In a high frequency amplifier for amplifying a received signal, a signal bypass path for bypassing the received signal without passing through the high frequency amplifier, and a signal path switching means for switching a path of the received signal between the high frequency amplifier and the signal bypass path An amplifying section, a level detecting means for detecting a signal level of the received signal, a reference voltage device for outputting a preset reference voltage signal, a received level detection output from the level detecting means and the reference voltage device And a comparator that outputs the result as a comparison determination signal to the control unit, and the comparison determination signal. A power switch controlled by a voltage control signal output from the control unit based on the above, and when the signal received by the antenna is at a level that does not require amplification by a high frequency amplifier, the control unit controls the power supply. A voltage control signal for turning off the switch is output, and the power supply to the high frequency amplification unit is stopped, and based on this, a signal switch in the high frequency amplification unit routes the reception signal from the high frequency amplifier to the signal bypass route. A wireless communication device characterized by switching to. 2. The wireless communication device according to claim 1, wherein the level detecting means is an envelope detector including a logarithmic amplifier and an envelope detector.