JPS5814112B2 - direct phase regenerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a direct phase regeneration device that directly regenerates a digital phase modulated wave containing noise in a carrier band.

Since the operating frequency of this type of conventional direct phase regenerator is low, it is necessary to convert a signal in a radio frequency band to a frequency band lower in the operating range of the direct phase regenerator.

Therefore, in order to manufacture a wireless repeater using a direct phase regenerator, the frequency converter and the direct phase regenerator had to be designed separately.

In order to solve these drawbacks, the present invention enables direct phase regeneration to be performed simultaneously with frequency conversion, and will be described in detail below with reference to the drawings.

FIG. 1 shows an example of a direct phase regeneration device according to the present invention, in which a two-phase phase modulated input signal from an input terminal 11 is supplied to a frequency converter 12, and a first local signal having the same frequency fO as that input signal, The output signal is frequency-converted by the second local signal having the same frequency f1, and the difference frequency component between the input signal and the output signal and the difference component between the input signal and the input signal are extracted as the output signal.

At this time, either the first local signal is synchronized with the input signal and used as the reference signal, or the second local signal is synchronized with the output signal and used as the reference signal.

In this example, the frequency f0 is the same as the radio frequency input signal frequency.
An oscillator 13 that oscillates at a frequency f1 is provided, and its oscillation output is frequency-mixed with a reference signal at a frequency f1 from a terminal 15 in a first conversion section 14 of a frequency converter 12.

This frequency f. The mixed output of ±f1 is given to the second conversion section 16 of the frequency converter 12 as a local signal, and the input terminal 1
The frequency f that has undergone a phase shift due to noise from 1.

frequency mixed with the two-phase phase modulated input signal. The output of the second conversion section 16 is passed through a bandpass F-wave device 17 whose passband has a frequency f1, and a phase-regenerated signal is taken out at its output terminal 18.

Now frequency f.

If the phase of the input signal of changes due to noise by φ, COS (
2π fat +φ).

On the other hand, the signal output of the first converter 14 is
When the frequency is mixed with , the following equation is obtained.

cos(2πfot+φ) {cos2π(fo+f
l) t+ cos 2π( fo+ f1)t }
(1) The output of equation (1) is passed through the P-wave device 17, and only the component of the station wave number fl is extracted as an output signal.

cos(2πf1t+φ)+cos(2πf1t-φ)
=2cosφ'COS2πf1t (2) Formula (
As shown in 2), the output signal is a signal fixed to O or π phase depending on the phase of the input signal, that is, a phase reproduction signal is obtained.

The local signal applied to the terminal 15 is a reference signal whose phase and frequency are fixed to the output signal, and this reference signal is produced, for example, with the configuration shown in FIG. 2.

That is, if the reproduced signal obtained at the output terminal 18 is an n-phase phase modulated wave, the frequency is multiplied by n in the multiplier circuit 21, and the unmodulated signal is supplied to the phase detector 22.

On the other hand, the output of the voltage controlled oscillator 23 is applied to the terminal 1 as a reference signal.
5, the frequency is multiplied by n in the multiplier circuit 24, and the signal is supplied to the phase detector 22, where the phase difference with the output of the multiplier circuit 21 is detected.

After the detected phase difference is amplified by the amplifier 25,
The signal is applied as a control signal to the voltage controlled oscillator 23 through the loop filter 26, and the oscillator 23 is phase-locked to the reproduced signal at the output terminal 18.

This technique is previously known as reference carrier extraction, and it is also possible to use reference carrier extraction methods other than that shown in FIG.

Furthermore, in the circuit shown in FIG. 1, if the signal applied from the terminal 15 is synchronized with the frequency f0 of the input signal from the input terminal 11, and the oscillation frequency of the oscillator 13 is set to the frequency f1 of the output signal, the phase will be the same. You can get a regeneration effect.

In this case, the signal applied to the multiplier circuit 21 in FIG. 2 may be obtained by branching off the signal applied to the input terminal 11 in FIG. 1.

The frequency converter 12 may be constructed by adding the input signal, the signal from the oscillator 13, and the signal from the terminal 15 to one conversion section, as shown in FIG.

FIG. 4 shows an example in which the present invention is implemented in a direct phase regeneration device for a four-phase phase modulated wave.

FIG. 5 shows a vector diagram explaining this operation.

The symbols a, b, c, d, e, f shown in Fig. 4 indicate the signals of each part. The vectors of these signals a to f are shown in Fig. 5 as A,
They are shown in correspondence as B, C, D, E, and F.

The four-phase phase modulated wave a from the input terminal 11 is the hybrid 2
At step 7, the signal is branched into two, and the branched outputs at this time become signals b and c whose phases are shifted by 90 degrees from each other, as shown in FIG. 5B and C.

These are supplied to frequency converters 16a and 16b, respectively, and the oscillation output f obtained by the converter 14.

and the signal f1 at the terminal 15, and the frequency is mixed with the difference component between the signal f1 and the signal f1 at the terminal 15.

From the conversion outputs of these converters 16a and 16b, the frequency f1
components are extracted by p-wave generators 17a and 17b, respectively.

The outputs d and e of the P-wave generators 17a and 17b are phase-regenerated into two-phase modulated waves having phases of 0 and π according to the modulated wave as explained in FIG. (see E).

In order to return these two-phase phase modulated waves d and e to four-phase phase modulated waves, the outputs of the filters 17a and 17b are
It is synthesized in 8.

At the time of this synthesis, if the phases are shifted by 90 degrees and the signals are synthesized as shown in FIG.

If the phase of this branched output does not shift by 90 degrees in the hybrid 27, a 90 degree phase shifter is inserted on one of the output sides, or the converter 16a, 1 which is output from the converter 14
An output equivalent to that described above can also be obtained by shifting the phase of the carrier wave supplied to one of the carriers 6b.

As explained above, the present invention obtains a direct phase regeneration effect using only a frequency converter without using a complicated circuit configuration or a direct phase regenerator that requires adjustment, so the circuit configuration is simplified and , it has the advantage of being able to perform transmission frequency conversion by utilizing the fact that the input and output signal frequencies are different.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a direct phase regeneration device according to the present invention, FIG. 2 is a block diagram showing an example of a reference carrier extraction method, and FIGS. 3 and 4 are direct phase regeneration devices according to the present invention, respectively. A block diagram showing another embodiment of the device,
FIG. 5 is a vector diagram for explaining the operation of FIG. 4. 11... Input terminal, 12... Frequency converter, 13... Oscillator, 14, 16, 16a, 16b... Frequency converter, 18... Output terminal, 27, 28... Hybrid.

Claims (1)

[Claims] 1. An oscillator that oscillates at a frequency equal to the frequency of the input signal or output signal, a circuit for obtaining a reference signal that is phase-synchronized with the output signal or input signal, and the input signal, the output of the oscillator, and the reference signal are supplied. a frequency converter;
A direct phase regenerator comprising a filter that selects a frequency component of the output signal from the frequency converter to obtain a regenerated output.