JPS5827699B2 - Signal transmission/reception method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a signal transmission and reception method in an angle modulation transmission and reception device.

Conventionally, this type of transceiver has been constructed as shown in FIG. 1, for example.

The receiver side includes an antenna 1, a high frequency amplifier 2, a first mixing circuit 3, a first local oscillation circuit 4, a multiplier circuit 5, a first intermediate frequency circuit 6, a second mixing circuit γ, a second local oscillation circuit 8, a second It is composed of an intermediate frequency circuit 9 and a demodulation circuit 10.

The transmitter side is composed of an oscillation circuit 11, a modulation circuit 12, a multiplier circuit 13, a power amplification circuit 14, and an antenna 15.

In such a configuration, a signal at the reception frequency fR is amplified by the high frequency amplifier circuit 2 and supplied to the first mixing circuit 3.

A signal obtained by multiplying the frequency oscillated by the first local oscillation circuit 4 by a multiplier circuit 5 is supplied to the first mixing circuit 3, and the signal at the receiving frequency fR is mixed with the output of the multiplier circuit 5. 1 intermediate frequency.

This signal is amplified by the first intermediate frequency circuit 6, then mixed with the frequency oscillated by the second local oscillation circuit 8 in the second mixing circuit 7, and reduced to the second intermediate frequency.

The signal dropped to the second intermediate frequency is amplified by the second intermediate frequency circuit 9 and then demodulated to the audio frequency by the demodulation circuit 10.

On the other hand, on the transmitter side, after the oscillation output from the oscillation circuit 11 is modulated by the modulation circuit 12, the transmitting frequency f is
multiplied by T, amplified by the power amplification circuit 14, and sent to the antenna 15.
Send from.

In this way, the conventional device requires three oscillation circuits, as well as a high frequency amplifier circuit 2, a first mixing circuit 3, and a first local oscillation circuit 4.
, the multiplier circuits 5, 13, the power amplifier circuit 14, etc. occupy a large area and consume a large amount of current.

In particular, when the radio frequency is high, the number of multiplication orders and amplification stages increases, resulting in an increase in current consumption.

For example, if the 2CH2 band is the radio frequency frequency band, these parts will occupy the majority of the transmitting/receiving device including other audio circuits and control circuits.

The second example shows another conventional example, and the same parts as those in FIG.
The frequency interval i, fT, rRl for transmission and reception is selected as the first intermediate frequency for reception, and the oscillation circuit for transmission and reception is shared by the oscillation circuit 11.

Therefore, in the case of FIG. 1, there are two oscillation circuits that require high stability, namely the first local oscillation circuit 4 and the oscillation circuit 1.
1, but the method shown in FIG. 2 has the advantage of being economical because only the oscillation circuit 11 is required.

However, even in the system shown in Figure 2, the multiplier circuit, which occupies a considerable portion of the space and current consumption, is the same as in the case of Figure 1, so there is little improvement in terms of size and current consumption. There was a problem that it was not done.

This invention was made in view of the above points, and by changing the frequency configuration of the transceiver in an angle modulation transmitting/receiving device having a superheterodyne receiver, the high frequency section can be shared, reducing the size of the entire device and reducing current consumption. It is an object of the present invention to provide a transmission/reception method that can be made small and economical.

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

FIG. 3 shows an embodiment of the present invention, in which 20 is a receiving antenna, 21 is a transmitting antenna 22 is a first mixing circuit, and 23 is a receiving antenna.
is a second mixing circuit, 24 is a distributor, 25 is a multiplier circuit, 26
27 is a phase modulation circuit, 27 is a first oscillation circuit, 28 is a multiplication circuit, 29 is a mixing circuit, 30 is a bandpass filter circuit, 31 is a mixing circuit, 32 is a second oscillation circuit, 33 is a modulation signal input terminal, 34 35 is a high frequency amplifier circuit, 35 is a power amplifier circuit, 36 is a fourth intermediate frequency circuit, 37 is a second intermediate frequency circuit, and 38 is a demodulation circuit, and their connection relationship is as follows.

That is, the oscillation circuit 27 is connected to the first input terminal of the phase modulation circuit 26 and also to the first input terminal of the mixing circuit 31.

A modulated signal such as audio is supplied to the second input terminal of the phase modulation circuit 26 via a terminal 33.

Further, the oscillation circuit 32 is connected to a second input terminal of the mixing circuit 31, and the output terminal of the mixing circuit 31 is connected to the first input terminal of the mixing circuit 29 via the bandpass filter circuit 30.

The output terminal of this mixing circuit 29 is connected to the second
It is connected to the first input terminal of the mixing circuit 23.

Further, the output terminal of the phase modulation circuit 26 is connected to a second input terminal of a mixing circuit 29 and is also connected to an input terminal of a distributor 240 via a multiplier circuit 25.

A first output end of this divider 24 is connected to the transmission antenna 21 via a power amplification circuit 35, and a second output end is connected to one input end of the fourth mixing circuit 22.

The receiving antenna 20 is connected to the other input terminal of the first mixing circuit 22 via a high frequency amplification circuit 34, and the output terminal thereof is connected to the second mixing circuit 23 via a first intermediate frequency circuit 36.
is connected to the second input terminal of the.

The output end of this second mixing circuit 23 is connected to a second intermediate frequency circuit 37.
It is connected to the demodulation circuit 38 via.

In such a configuration, the carrier wave generated by the oscillation circuit 21 is reflected in the phase modulation circuit 26, modulated by a modulation signal such as audio, and then multiplied by the multiplier circuit 25 to a desired frequency.

This multiplied output is distributed by the distributor 24, a part is transmitted from the transmitting antenna 21 as a transmission wave, and one part is transmitted from the first
It is output as the first local signal of the mixing circuit 22.

The first mixing circuit 22 mixes the output of the distributor and the received wave of the receiving antenna 20, and outputs the same wave number in the first half.

The above operation can be expressed numerically as follows.

The carrier wave of the oscillation circuit 27 is □□□ωIL', terminal 3.
3, the modulation sensitivity of the phase modulation circuit 26 is m, and the multiplication order of the multiplier circuit 25 is n.

Further, the amplitudes in the display of the output signals of each section are omitted here because they have no important meaning.

The output of the phase modulation circuit 26 is as follows.As is clear from equation (3), the first intermediate frequency output includes its own modulation signal, and when this 11 demodulation is performed, it is observed as sidetone in a wireless telephone that performs simultaneous transmission and reception. will be done.

This self-modulated signal is canceled by the second mixing circuit 23, and the circuit operation for obtaining the second local signal of the second mixing circuit 23 will be described below.

The output of the oscillation circuit 32 is mixed with the output of the oscillation circuit 2T by the mixing circuit 31, and a signal representing the sum or difference of the two signals is extracted by the bandpass filter circuit 30.

The signal extracted by the bandpass filter circuit 30 is mixed with the output signal of the phase modulation circuit 26 in a mixing circuit 29, and a signal representing the difference between these two signals is extracted.

Here, whether the sum or difference signal is extracted by the bandpass filter circuit 30 is determined so that the second mixing circuit 23 cancels its own modulation signal.

That is, if the reception angular frequency is ωR1, the first local oscillation angular frequency is nω1L, the first L angular frequency is ω1L, and the second local oscillation angular frequency is nω2L, then nωI L > 0)Rs
When n(,,2L 〉ω1■ and nωI L > ω
R* When nωzL<”iI, the difference signal, and nω
1, when ωB, nω2L〉ωII, and nωl, ω
When R, nω2 and ω1, the sum signal is selected.

The output of the mixing circuit 29 taken out in this way is
is multiplied by

This multiplication circuit 28 has the same multiplication order as the multiplication order of the multiplication circuit 25.

Therefore, the output of the mixing circuit 29 is multiplied by n in the multiplier circuit 28 and outputted as the second local signal of the second mixing circuit 23.

The above operation can be expressed numerically as follows.

Here, only the cases of n, ω□ and ωR, and nω2 and ω1L are shown, but the other cases described above are completely similar.

The output of the oscillation circuit 32 is ■ω2Lt The output of Goheji 31 is Then, the mixture becomes.

Further, the output of the filter circuit 30 is set to select the sum signal from the above equation (4).

Further, the output of the mixing circuit 29 is the one from which the difference signal is taken out, and from the above equation (1), it becomes as follows.

Also, the output of the multiplier circuit 28 is becomes.

Accordingly, the output of the second mixing circuit 23 is obtained from the above equation (3) because the difference signal is extracted and nω2 and ω1 are selected.

As is clear from this equation (8), the second mixing circuit 2
In the output of No. 3, the self-modulated signal is canceled and no sidetone is observed.

In the case of this embodiment, the multiplication order of the multiplier circuit 28 is the same as that of the multiplier circuit 25 for obtaining a high frequency, but since the frequency is low and the output power can be low, the circuit configuration can be relatively simple, and the effects of the present invention can be achieved. is not damaged.

According to this embodiment, the radio frequency is changed by the oscillation circuit 27.
This can be achieved by changing only the oscillation circuit 27, the phase modulation circuit 26, the multiplier circuit 25, the distributor 24, and the transmission antenna 21, since there is no mixing circuit in the transmission system.
Since the configuration is the same as that of a general transmitter, spurious radiation from the transmitter can be suppressed to the same level as a general transmitter.

Furthermore, since there is no mixing circuit in the transmission system, there is no conversion loss, and transmission output can be obtained with power efficiency equivalent to that of a general transmitter.

Note that even if this embodiment is slightly modified and the mixing circuit 31 mixes the output with the output of the oscillation circuit 26, and then the mixing circuit 29 mixes the output with the output of the oscillation circuit 27, the frequency relationship will remain the same as in this embodiment. However, this embodiment is superior in that the bandpass filter circuit 30 has no effect on the modulated signal component.

Next, another embodiment of the present invention will be explained with reference to FIG.

In FIG. 4, parts that are the same as those in FIG.

The carrier wave generated by the oscillation circuit 27 is transmitted to the phase modulation circuit 26.
After being modulated by , it enters a multiplier circuit 25 and a mixing circuit 31 .

The output multiplied by the multiplier circuit 25 enters the distributor 24, a part of which is transmitted from the transmitting antenna 21, and a part of which is output as the first local signal of the first mixer 22.

Further, the mixing circuit 31 mixes the oscillation output from the oscillation circuit 32 and the modulation signal, outputs the mixed signal, and sends the mixed signal to the multiplier circuit 28.

This multiplier circuit 28 multiplies the mixed output and outputs it to the second mixing circuit 23 as a second local signal.

In this case, the radio frequency is selected so that the first intermediate frequency is 17"R, 7"TI.

Here, for example, the oscillation frequency from the oscillation circuit 27 is fl, the oscillation frequency from the oscillation circuit 32 is 12, and the multiplier circuit 25
, 28, and the first and second local frequencies that are input to the mixing circuit 22゜23.31 that extracts the difference frequency are placed on the upper side, and the oscillation frequency of the oscillation circuit 32 is placed on the lower side. The second intermediate frequency fLF is as follows.

Therefore, fIF has no relation to f1 which is modulated in principle, the modulation of transmission is canceled in reception, and only the modulation of the normal received wave JR is demodulated.

Further, FIG. 5 shows still another embodiment of the present invention, and the third embodiment shows a third embodiment of the present invention.
Components that are the same as those in FIG.

The output of the oscillation circuit 27 is multiplied by a multiplier circuit 43 and then input to a mixing circuit 40 .

On the other hand, the output of the oscillation circuit 32 is modulated by the modulation circuit 26, multiplied by the multiplier circuit 28, and then enters the mixing circuit 40 via the amplifier circuit 41. Enter 23.

The mixed output of the mixing circuit 40 enters the distributor 24, is output as a transmission wave, and becomes the reception first local frequency, as in each of the embodiments described above.

In the case of FIG. 5, for example, the oscillation frequency of the oscillation circuit 27 is 13, the oscillation frequency of the oscillation circuit 32 is f4, and the multiplier circuit 43
The multiplier of the multiplier circuit 28 is l, the multiplier of the multiplier circuit 28 is m, and the first
Assuming that the third local frequency is the upper side and the output of the mixing circuit 40 is the frequency of the sum of the two human powers, the second intermediate frequency fIF is as follows.

Therefore, the second intermediate frequency fIF has no relation to f4 which is being modulated in principle, and only the normal received wave fR is demodulated as in the example of FIG.

As explained above, according to the present invention, in an angle modulation transmitting/receiving device having a superheterodyne receiver, the number of high frequency multiplier circuits in the transmitter/receiver can be reduced compared to the conventional one.
In addition, since the number of oscillation circuits can be kept to a minimum, significant effects can be obtained in reducing the size of the device and reducing current consumption, and this is particularly effective in transmitting and receiving devices that use high radio frequencies.

[Brief explanation of drawings]

1 and 2 are configuration diagrams for explaining a conventional transmission and reception system, FIG. 3 is a configuration diagram showing an embodiment of the present invention, and FIG. 4 is a configuration diagram showing a second embodiment of the invention. FIG. 5 is a configuration diagram showing a third embodiment of the present invention. 20... Receiving antenna, 21... Transmitting antenna, 22... First mixing circuit, 23...
...Second mixing circuit, 26...Modulation circuit, 27
. . . first oscillation circuit, 32 . . . second oscillation circuit, 25, 28, 43 . . . multiplier circuit.

Claims (1)

[Claims] 1. An angle modulation transmitting/receiving device having a superheterodyne receiver, which obtains a transmission signal angle-modulated by its own modulation signal, has its own angle modulation component in this transmission signal, and has its own angle modulation component in this transmission signal. a first means for obtaining a low frequency signal with respect to a transmission signal; a second means for branching a part of the transmission signal and supplying it to a first mixing circuit of the receiver as a first local signal; and third means, which is located after the first mixing circuit of the receiver and cancels its own angle modulation component contained in the received signal after frequency conversion by the low frequency signal from the first means. A signal transmission and reception method characterized by: 2. The signal transmission and reception system according to claim 1, wherein the third means is a second mixing circuit of a receiver. 3. The first means includes a first oscillation circuit, a modulation circuit that angle-modulates the output signal of the first oscillation circuit with its own modulation signal, and a first multiplier that multiplies the output signal of the modulation circuit by a predetermined order. means having a circuit, a second oscillation circuit, a third mixing circuit for mixing the output signal of the second oscillation circuit and the output signal of the first oscillation circuit, and an output signal of the third mixing circuit. and the output signal of the modulation circuit.
and means having a second multiplier circuit for multiplying the output signal of the fourth mixer circuit to the same order as the first multiplier circuit, the first multiplier circuit and the second multiplier circuit of each means. 3. The signal transmission and reception system according to claim 1, wherein the transmission signal and the low frequency signal are obtained from a multiplier circuit.