JPH0964765A - Radio receiving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the radio receiver by which characteristics of signals in each reception band are fully derived. SOLUTION: A signal received by an antenna 1 is frequency-converted by an RF mixer section corresponding to a reception band of each band circuit section 3 via a signal changeover device 2 selected and connected depending on a reception band of the reception signal and fed to an IF section 6 via a signal changeover device 4 selected and connected depending on the reception band. In the inside of each band adjustment semiconductor 8, the signal is adjusted by any of semi-fixed resistors 8a to 8c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio receiver having a plurality of reception bands.

[0002]

2. Description of the Related Art Conventionally, in a radio receiving apparatus having a plurality of reception bands and receiving signals wirelessly, each reception band circuit unit for frequency conversion of signals of each reception band and a common circuit for signal adjustment. Section. Here, specifically,
FIG. 8 shows a schematic configuration of a wireless reception device having three reception signal bands, that is, reception bands.

In the radio receiving apparatus of FIG. 8, the signal received by the antenna 41 is passed through the signal switch 42 which is switched and connected according to the receiving band, and the RF mixer section 43a corresponding to each of the three receiving bands is provided. , 43b, 43c, the RF of any one of the circuit units 43 for each band.
Sent to the mixer section. In the RF mixer section, the received signal sent is converted into a constant frequency and sent to the common circuit section 45 via the signal switch 44 which is switch-connected according to the reception band.

Specifically, for example, the RF mixer section 43a
When a signal in a band to be signal-processed is received by the signal switching devices 42, 44, the terminals 42a, 4 respectively.
4a is switched and connected. As a result, the received signal from the antenna 41 is frequency-converted by the RF mixer unit 43a via the signal switcher 42 switched and connected to the terminal 42a, and then transmitted through the signal switcher 44 switched and connected to the terminal 44a. It is sent to the common circuit section 45.

Similarly, the RF mixer section 43b or RF
Regarding the reception signal to be signal-processed by the mixer unit 43c, the signal switching devices 42 and 44 are connected to the terminals 42b and 44b or the terminals 42c and 44c, respectively, and are received via the signal switching device 42b or the signal switching device 42c. Signal is R
The frequency is converted by the F mixer section 43b or the RF mixer section 43c and sent to the common circuit section 45 via the signal switch 44b or the signal switch 44c.

The common circuit section 45 has an intermediate frequency (I
It comprises an IF unit 46 and an adjusting unit 47 for amplifying F). The adjusting unit 47 is a semi-fixed resistor, and the reception signals of the three bands are amplified by the IF unit 46 based on the adjustment by the adjusting unit 47. In this way, the adjusting unit 47
It is commonly used for the three reception bands.

[0007]

By the way, in the above-mentioned radio receiver, the characteristics of the band circuit section 43 are not uniform due to variations in the characteristics of the components. Therefore, the output signal from each band circuit unit 43 has an optimum value for each reception band. However, the signals of the respective reception bands are adjusted to be the same by the adjustment unit 47 commonly used in the common circuit unit 45. That is, the signal of each reception band is adjusted to a value that does not cause a problem at the time of reception. As a result, it is not possible to maximize the characteristics of the signals in each reception band.

Therefore, in view of the above situation, the present invention provides a radio receiving apparatus capable of maximizing the signal characteristics of each reception band.

[0009]

A radio receiving apparatus according to the present invention has a common circuit section for commonly processing signals of a plurality of reception bands, and the common circuit section adjusts a level for each reception band. It is provided with an adjusting unit.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of an embodiment of a radio receiving apparatus according to the present invention. This wireless receiver is
A common circuit section 5 for commonly processing signals of a plurality of reception bands
The common circuit section 5 includes an adjusting section 8 for each band, which is an adjusting section for adjusting the level for each reception band.

Specifically, the radio receiver of FIG. 1 is compatible with three reception bands, and the signal received by the antenna 1 is passed through the signal switch 2 which is switch-connected according to the reception band. Then, the signal is sent to one RF mixer unit in each band circuit unit 3 including the RF mixer units 3a, 3b, and 3c corresponding to the three reception bands. In the RF mixer section, the received signal sent is converted into a constant frequency and sent to the common circuit section 5 via the signal switch 4 which is switch-connected according to the receiving band.

Specifically, for example, when a signal in a band to be signal-processed by the RF mixer unit 3a is received, the signal switching units 2 and 4 are switched and connected to the terminals 2a and 4a, respectively. As a result, the received signal from the antenna 1 passes through the signal switch 2 which is switch-connected to the terminal 2a,
After being frequency-converted by the F mixer 3a, the signal is sent to the common circuit unit 5 via the signal switch 4 which is switch-connected to the terminal 4a.

Similarly, with respect to the received signal to be signal-processed by the RF mixer unit 3b or the RF mixer unit 3c,
The signal switchers 2 and 4 include terminals 2b and 4b or terminals 2c and 4 respectively.
The signal received through the signal switch 2b or the signal switch 2c is connected to the RF mixer 3b or R.
The frequency is converted by the F mixer 3c and sent to the common circuit unit 5 via the signal switch 4b or the signal switch 4c.

The common circuit section 5 has an intermediate frequency (IF).
An IF unit 6 for amplifying each band, an adjusting unit 8 for each band including a plurality of semi-fixed resistors 8a, 8b, 8c corresponding to the plurality of receiving bands, and a plurality of half units in the adjusting unit 8 for each band. The fixed resistor 8a, 8b, 8c is composed of a switch 7 for switching and selecting.

The output signal from each band circuit section 3 is sent to the IF section 6 in the common circuit section 5. Where I
The output from the semi-fixed resistor, which is switched and selected according to the reception band, in the band adjustment unit 8 is input to the F unit 6 via the switch 7. For example, if the received signal is processed by the RF mixer section 3a in the circuit section 3 for each band, the switch 7 is switched and connected to the terminal 7a, and the adjustment for each band is connected to the terminal 7a. The semi-fixed resistor 8a in the section 8 is switched and selected. As a result, in the IF section 6, the output signal from each band circuit section 3 is adjusted and amplified by the semi-fixed resistor 8a in each band adjustment section 8 and then output.

Similarly, if the received signal is processed by the RF mixer section 3b or the RF mixer section 3c in each band circuit section 3, the switch 7 is connected to the terminal 7b or the terminal 7c.
The semi-fixed resistor 8b or the semi-fixed resistor 8c in each band adjusting unit 8 that is switched and connected to the terminal 7b or the terminal 7c is switched and selected.

As a result, in the IF section 6, the output signals from the RF mixer sections 3a, 3b, 3c in the band circuit section 3 are switched and selected according to the reception band, and the band adjustment sections are selected. It is output after being adjusted and amplified by the semi-fixed resistor in 8.

Next, as a radio receiving apparatus according to the present invention,
A schematic configuration of the receiving device of the first wireless device is shown in FIG. 2 and will be described below.

Specifically, this wireless device is a specific low-power wireless device of a full-duplex communication system, so-called duplex system, in which mutual communication is performed by simultaneous transmission and reception of signals. The duplex system has two bands, and a wireless device capable of receiving signals in the two bands requires two receiving units.

Therefore, in the receiving device of the first radio equipment of FIG. 2, the signal received by the antenna 11 is passed through the signal switch 12 which is switch-connected to the terminal 12a or the terminal 12b according to the reception band. It is sent to the RF mixer unit 13a or the RF mixer unit 13b. This RF mixer 13a or R
The F mixer 13b frequency-converts the received signal sent. This RF mixer section 13a or RF mixer section 13
The output signal from b is output to the terminal 14 according to the reception band.
It is sent to the IF section 15 via the signal switch 14 which is switch-connected to the terminal a or the terminal 14b.

Here, the IF section 15 includes a squelch adjusting section 17 for adjusting the squelch output and a carrier sense adjusting section 19 for adjusting the carrier detection output, respectively.
6 and the switch 18 are connected.

Specifically, the squelch adjusting unit 17 includes two semi-fixed resistors 1 corresponding to two reception bands, respectively.
7a and 17b, and the switching device 16 is switched and connected to the terminal 16a or the terminal 16b in accordance with the reception band, whereby the semi-fixed resistor 17a or the semi-fixed resistor 17 is connected.
b is switched and selected. That is, in the IF unit 15, the RF mixer unit 13a or the RF mixer unit 13 is controlled by the semi-fixed resistor 17a or the semi-fixed resistor 17b in the squelch adjusting unit 17 which is switched and selected according to the reception band.
The squelch output of the signal from b is adjusted.

The carrier sense adjusting section 19 is also
It is composed of two semi-fixed resistors 19a and 19b respectively corresponding to the two reception bands, and the switching device 18 is switch-connected to the terminal 18a or the terminal 18b according to the reception band, whereby the semi-fixed resistors 19a are connected. Alternatively, the semi-fixed resistor 19b is switched and selected. That is, in the IF unit 15, the RF mixer unit 13a or R is switched by the semi-fixed resistor 19a or the semi-fixed resistor 19b in the carrier sense adjusting unit 19 which is switched and selected according to the reception band.
The carrier detection output of the signal from the F mixer 13b is adjusted.

A carrier sense detecting circuit 20 is connected to the carrier sense adjusting section 19. The output for adjusting the carrier detection output from the carrier sense adjusting unit 19 is sent to the carrier sense detection circuit 20, and this carrier sense detection circuit 20 controls whether or not to prohibit the sending of the carrier signal.

Here, the squelch adjustment by the squelch adjusting section 17 will be specifically described.

A schematic structure of a squelch circuit for adjusting the squelch is shown in FIG. 3. In this squelch circuit, a speaker that outputs a received signal when there is no received signal or when the received signal is very weak. Control is performed so that noise is not output from the output device such as.

Specifically, the signal received by the antenna 31 is detected by the receiving circuit 32 and sent to the mute circuit 37. At the same time, the receiving circuit 32 extracts noise from the detected signal. This noise is generated by the amplifier 33
To the rectifier circuit 34 after being amplified by the rectifier circuit. In this rectifying circuit 34, direct current is extracted from the sent noise and sent to the comparator 35. In the comparator 35, it is detected whether or not the sent direct current is input at a level higher than a preset level by the adjustment of the variable resistor 36. As a result, when a signal having a level equal to or higher than the set level is detected, the signal is sent from the comparator 35 to the mute circuit 37.

In this way, in the comparator 35,
The level of the signal detected by the receiving circuit 32 is adjusted, and the mute circuit 37 is controlled so that the sound output from the speaker 38 is stopped when the noise level of the signal from the receiving circuit 32 becomes large.

FIG. 4 shows the relationship between the level adjustment and the apparent sensitivity when the level of the received signal is adjusted by the squelch circuit described above.

By adjusting the level so as to stop the sound output from the speaker 38 at the time of no signal input, that is, when the noise is maximum, the muting does not work when the level adjustment is large, as shown by x in FIG. While the mute becomes unstable when shown, the noise is reduced and the sound is output from the speaker 38 when the point A is shown, and the best adjustment is made to maximize the apparent sensitivity. After this,
When the level adjustment is made smaller, the level adjustment is such that the sound output from the speaker 38 remains stopped even if the noise is reduced. For example, the apparent sensitivity at the point B is the point A. Worse than

In the conventional radio receiver, the squelch of signals in a plurality of reception bands is adjusted by using a common squelch adjusting unit. Therefore, for example, as shown in FIG.
The signals of the _two reception bands R ₁ and R ₂ are subjected to level adjustment by avoiding the unstable portion indicated by × and the dotted line, and therefore the level adjustment point is S. As a result, the level of the signal in the reception band R ₁ can be adjusted to the best point C ₁ , but the level of the signal in the reception band R ₂ cannot be adjusted to the best point, which is less sensitive than the best point. Adjust to point C ₂ .

On the other hand, if a squelch adjusting unit is provided for each receiving band as in the receiving device of the radio equipment shown in FIG. 2, as shown in FIG. 6, the level adjustment of the signal in the receiving band R ₁ is performed. The point can be S _1, and the level adjustment point of the signal of the reception band R ₂ can be S ₂ . As a result, the level of the signal in the reception band R ₁ can be adjusted to the best point C _1, and the level of the signal in the reception band R ₂ is also the best point C _3.
Can be adjusted to.

Next, as a radio receiving apparatus according to the present invention,
A schematic configuration of the receiving device of the second wireless device is shown in FIG. 7 and will be described below. In the receiving device of the second wireless device in FIG. 7, each unit indicated by the same reference numeral as the receiving device of the first wireless device in FIG. 2 performs the same operation as the operation described in FIG. Therefore, detailed description is omitted.

IF unit 1 of the receiving device of the second wireless device
5, the squelch adjusting unit 17 of FIG.
(Analog / digital) converter 23 is connected,
An A / D converter 22 is connected instead of the carrier sense adjusting unit 19 of FIG. The analog voltage of the squelch signal is converted into a digital signal by the A / D converter 23 and is sent to the control section 24.
Then, the analog voltage of the carrier sensing signal is converted into a digital signal and sent to the control unit 24. As a result, the control unit 24 adjusts the squelch output and the carrier detection output using the squelch signal and the carrier sense signal, respectively.

As described above, in the receiving apparatus of the first radio equipment of FIG. 2, the squelch output and the carrier detection output are adjusted by the hardware configuration of the squelch adjusting unit 17 and the carrier sense adjusting unit 19, but in FIG. In the receiving device of the second wireless device, the squelch output and the carrier detection output are adjusted by the software of the control unit 24.

[0037]

As is apparent from the above description, the radio receiving apparatus according to the present invention has a common circuit section for commonly processing signals of a plurality of reception bands, and the common circuit section is the reception circuit. Since it is possible to adjust the signal level for each reception band by including the adjustment unit that adjusts the level for each band, the maximum characteristics of the signal in each reception band, that is, as designed The characteristics can be brought out.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of a wireless reception device according to the present invention.

FIG. 2 is a schematic configuration diagram of an embodiment of a receiving device of a first wireless device.

FIG. 3 is a schematic configuration diagram of a squelch circuit.

FIG. 4 is a diagram for explaining the relationship between level adjustment and apparent sensitivity.

FIG. 5 is a diagram for explaining a case where a squelch adjustment unit common to each band is provided.

FIG. 6 is a diagram for explaining a case where a squelch adjusting unit is provided for each band.

FIG. 7 is a schematic configuration diagram of an embodiment of a receiving device of a second wireless device.

FIG. 8 is a schematic configuration diagram of an embodiment of a conventional wireless reception device.

[Explanation of symbols]

 1, 11 Antennas 2, 4, 12, 14 Signal switching device 3 Each band circuit part 5 Common circuit part 6, 15 IF part 7, 16, 18 Switching device 8 Each band adjusting part 13a, 13b RF mixer part 17 Squelch Adjusting unit 19 Carrier sense adjusting unit 20 Carrier sense detecting circuit 22, 23 A / D converter 24 Control unit

Claims (4)

[Claims] 1. A radio receiving apparatus having a plurality of reception bands, comprising a common circuit section for commonly processing signals of the plurality of reception bands, wherein the common circuit section adjusts a level for each of the reception bands. A radio receiving apparatus comprising an adjusting unit. 2. The adjusting unit uses a plurality of semi-fixed resistors corresponding to the plurality of reception bands, and switches and selects the plurality of semi-fixed resistors according to switching of the plurality of reception bands. The wireless receiving device according to claim 1, wherein 3. The radio according to claim 1, wherein the adjusting section includes a squelch adjusting section for adjusting a squelch output and a carrier adjusting section for adjusting a carrier detection output for each of the reception bands. Receiver. 4. The adjusting unit, for each reception band,
The squelch output and the carrier detection output are converted into digital signals and adjusted respectively.
The wireless receiving device described.