JPS5952952A - Circuit for reproducing reference carrier - Google Patents

Abstract

PURPOSE:To minimize the effect of DC drift component caused by temperature change, etc., by reducing the number of sections connected to DC in a base band processing section. CONSTITUTION:When, for example, a receiving 4-phase PSK modulated wave inputted into an input terminal 1 has a DC component, a signal, from which the DC component and DC drift component caused by temperature change, etc., are removed and which is proportional to sin2theta, is obtained from a high-pass filter 12 and sin4theta is obtained from an EX-OR 9. When the 4-phase PSK modulated wave is exclusively composed of DC components, the sin2theta from a multiple component extracting means 14 is blocked by the high-pass filter 12. Therefore, only cos2theta from squared value output waveform converting means 15 is inputted into the EX-OR 9 and a signal proportional to the cos2theta is outputted. In this case this is sufficient to make the operation because the receiving signal is exclusively composed of DC components.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical field of the invention The present invention relates to a reference carrier recovery circuit, and in particular to a multiphase PS
The present invention relates to a basic carrier wave regeneration circuit in the baseband band used in the central part of the claw radio device 1ffi using K modulation.

(2) The multiplex radio transmission system using aPsKf modulation has a larger amount of information per unit time than the wide modulation transmission system or the frequency modulation transmission system for the same frequency range, that is, the transmission speed is higher. Because it has the characteristic of being thick, it is used as an advantageous transmission method when transmitting a large amount of information within a certain band '1lin'.

多su P SK (Phase 5hift i(e
The ying Ci modulation method is a transmission method in which rn-bit information is digitally phase modulated onto the n-phase (n=2m) of a carrier wave.

When modulating the received PSK modulated wave, use the 4th digit of the reference carrier wave that has the same phase as the transmitted primary transmission wave and the received PSK modulated wave.
By comparing the phases of the modulated waves, the information and measurement of each bit is determined.

Therefore, for straw tone + Sl (transmission W'i, a base carrier wave with the same phase as the transmission wave is required, but on the transmission side, in order to eliminate the transmission 41Δ effect, level 1 (]) A method is used in which only PSKK and ii'J waves are transmitted without transmitting waves.

Therefore, the support %i 'frill was received in the counterclaim section 1) S K Henkan 1'4 wave from the,! :It is necessary to generate 4I'R shell transmission.

For this basic velocity wave 1) regeneration 1・d, there is a method using non-leg-shaped depression in the carrier f anti-frequency firefly, and a method using non-+ annotation operation in the baseband band for Au. % formula % and 1jfJ method is 4Fj method, inverse variation M
-J method, +1) modulation method, etc. These shinai types have a wide retraction range <m+Note, but it is possible to absorb the standard intrusion wave, but since the jh transmission frequency is low, the frequency is %j <, trough; 111i (, No. 4 processing and adjustment are not easy, and the configuration and manufacturing of No. 1 (II)
It's a rough 9-sided score, or 15.

On the other hand, H1
The Tsume ivi imaging wave transmission method used is Costas (CO8T
It is collectively called the Costas method because it includes a phase-locked loop called an AS) loop. This circuit system facilitates various 'lr4 processing in the baseband band/ζth frequency.

(3) Prior art 11iJ and problems Motomoto Nagisa et al. have already proposed this god's nine quasi IHi9, Δ waveform conversion circuit, in Application No. 1izu 56-212775. Such a basic urine transmission wave) 4) The regeneration 1-heat is made up of 44 circuits, which are 1M weaker than those of that size! g
lJ-ability.

quotient? J:'jJ:Tau'fJ, but this will be explained below with reference to FIG.

Figure 1 shows the base 31μ carrier wave 1.) raw lI-'l +16 for the 4-phase 1) S K modulated wave.
4 children, 2 is the 1st place 40 position θ support, 3 is 90°, +7 A
'0 device, 4 is the condolence 2 I M J1 tester, 5 is 1 le 1 exclusive logic A11 circuit (1st EX-OR'), 6 is 2 coming 11
μ circuit, 7 is a low-pass filter, 8 is a waveform converter, 9
is the second exclusive; i+, ii jJj /I'LI times! 1
Each (21st BX-0Ie), 10 is a loop filter, 1
1 is the 'Tun Oppressor Excavator (VCO). 11th εX
-0R5 and the low-pass 1ltl filter 7 are used as the first means 14 for extracting the 2-channel harmonic component, and the 2-111 circuit 6 and the waveform conversion circuit 8 are used to extract the 2-value of the second phase detector output. bird,
A means for converting the waveform of this square value output, that is, a 2nd value output waveform converting means 15, and a second EX-OR 9 constitute a second 2nd multiplication waveform component extracting means, respectively. 2y4 (The value circuit 6 is an absolute IUI that performs operations such as full-wave rectification of the input signal and finding its absolute value. It is possible to use circuits.

Sentence Tf currently input to input y114 child 1 44th P
If θ is the angle between the silver transmission of the S K-shaped d'J wave and the subcarrier generated by VCO II, then the first position is 411. The second phase detection is 7iii. The phase shifter 3 performs quadrature detection, and the first phase shifter 2
An output proportional to nθ is generated, and an output proportional to 40 is generated from the second phase four-wavelength wave generator 4.

When the signal θ is applied from the 132 phase detector 4 to the first EX-OR50 input terminal a, and the KH1 phase detector 25ino is applied to the input terminal b, the giax-OR5
Hazu no do 1] 1 old 'zu + 1irii ri 0 ('JJ-7-
Outputs υ-st++ 20. Next, by passing through seven phase inversion type low pass filters, a predetermined 2
Input sin 2θ, which is a subharmonic component.
I can do S. Here, by simultaneously providing the function of the low-pass filter 7 inside the first EX-OR 5, it is also possible to immediately generate sin 2θ at its output terminal.

The square value circuit 6 excludes the output θ output from the second phase shifter 4 and outputs the entire output 2θ, but cOs2θ=2θ2θ−1
Since there is a coefficient ω, the waveform converter 8 converts this ω
By simply doubling s20 and shifting the level by 1 in the negative direction, (2) from the 2θ output to (3)
2θ can be obtained. Here, by performing this conversion operation simultaneously inside the square value circuit 6, it is also possible to immediately generate αG2θ at its output 41.

The sin 2θ and cos 2 thus obtained
0 to the second EX-OR9; and find their exclusive logic 40, we get % Ail's first EX-O.
By the same operation as in R5, connect si to its output terminal.
n 40 can be output. Using the output 4j proportional to the wave 40 obtained in this way, the loop filter 10 is connected to the loop filter 10 and the VCO II is output to the receiver, and the 14-phase PSK is connected to the 17J wave. C4
It can be said that the A-carry-on wave was the same as the So-go-komi wave.

However, the standard carrier wave shown in Figure 1 of Section 2 ('')
The first two-component harmonic component extraction means 14 (IIL band filter 7) and the second two-component harmonic component extraction means 14 (IIL band filter 7)
1. 1L harmonic component extraction means (second EX-OR') 9, and the square i+1 output waveform transformation means 15 (waveform conversion circuit 8) and the second 2 m 1r'f Since the bond with W-(l'i', 2 EX-OR) 9 is a rotation υit bond, l[t
There was a problem that it was vulnerable to VTC drift.

(4) Purpose of the Invention The present invention is designed to determine the point 'T i'r[ between the above i [, + Takumi's reference carrier 1 generation circuit], and the above-mentioned 7. To prevent single-current coupling between open circuits and to reduce the influence of DC drift due to changes in temperature, etc.

(5) Structure of the Invention In order to accomplish the purpose of the above-mentioned problem, in the present invention, in a fundamental carrier wave endogenous circuit as shown in FIG. Extraction means and second double harmonic component i11
+ combination of output means, - or square value or absolute 111<
Either one of the output waveform converting means and the second double harmonic wave component extracting means is performed via a JbII curved filter. It is something.

(6) Embodiment of the Invention Hereinafter, one embodiment of the present invention will be explained with reference to FIG. 12゜131 −, j
: Indicates a high-pass filter in which only one of the filters is installed.

Hereinafter, for the sake of explanation, the first two-component harmonic component extracting means 14 (low" 8), the filter 7) and the second two-component harmonic component extracting means (
gi'c 2 EX-OR') 9 through the high-pass filter 12. The explanation will be given assuming that the high-pass filter 13 is not provided.

Now, the received 4-phase PSK modulated wave inputted to the input terminal 1 removes the DC component. In this case, the high-pass filter 12 has its DC component as well as a temperature change of 4+,
- IbJE of the 11f drift component due to si
'Ilt' which is proportional to n 2θ is 19. In the dark, the 21st! ; Input 5in4θ from X-0R9 output.

Also, if the received 44I IPSK modulated wave consists of only DC components, ! /I'; The capture 2θ from the second harmonic wave component extracting means 14 of 1 is stopped at 111 by the tracing filter 12, and the 21st! manually to EX-OR9)L
do not have.

Therefore, 躬2 EX-OR9 (l: i squared = -j output waveform conversion method j inverse 15 to 20 is input, therefore, 1 and 4 proportional to ω52θ are output. However, "Here's what I did" is input above x iba 44i + ps
The K modulated wave is it, i.

vll, it depends only on the ingredients, and it is the same as before (5
It is not necessary to generate 144 transfer waves based on 1+j% proportional to in4θ. It is possible to generate a transfer wave (.) which can sufficiently serve as a reference using the 2θ output from the above-mentioned 2-coat output waveform converting means 15.

This occurs not only when the full-d filter 12 is provided, but also when the square value output waveform conversion means 15 and the second double harmonic wave component extraction means (second EX-OR) are used.
The same applies to the case where the coupling with 9 is performed via the high-pass noirter 13.

That is, it is recommended to remove the high-pass filter 12, but if the high-pass filter 13 is provided, the direct current component as well as the drift component of the output from the square value output waveform converting means 15 can be removed. It is proportional to the residence 2θ. However, if a signal consisting only of DC components or 0 is input, the second EX-
Only the first 2, 5tn2θ of the ML harmonic component extraction means 14 is input to the OR9. However, if the received signal consists only of DC components as described above, this is sufficient to eliminate the operating force.

As described above, in the present invention, the second two-component wave extraction means 9 and the first two-component harmonic component extraction means 14 or the square one direct output waveform conversion means 15 are combined. The DC component is I
High-pass filter that stops JI 12. In this case, the passband of the r-region filter is determined by converting the DC component from the input stage to I.
A 47 degree one that stops IJI is sufficient, and it can be easily adjusted to 41'4 with a capacitor for cutting current components according to the circuit requirements.
can be achieved.

Further, the square value output waveform conversion means 15 is tf, 2
31! : Value circuit 6 (d, conventional early carrier wave regeneration circuit (
1), overuse of the absolute value circuit is possible.

In addition, on the double stream side, the double wave component extraction 11
j means: exclusive OR circuit (ICX-C)
Is this only the case where the sound is used?
In other words, as is already known, each of the 111 fathers of JJj, the S stone θr cos θ, each of the 2 stupefactions (or absolute 1 directness), 5 in 2 θ 1 part 2 θ, and the left of both. (((Yu2θ-5in20') =
Of course, it is also possible to extract the 2f)'H harmonic 1 component (22θ) of the input information signal by cos 2θ).

In addition, from the actual flow side as well, there is a double harmonic component extraction means and a
By multiplying the operation 1' by the multiplication 11=-di type output means by E length, the 4th number (IJ is not determined at the 44th position, and 2° (
(M≧2) It is clear that the fourth PSK friend d-wave reference transmitting and reproducing circuit is 1U.

(7) Effects of the invention As mentioned above, the present invention 9i-mei has a +! This was done by the inventors who provided a small circuit with 4 reference carrier waves;
The influence of DC drift components due to absorption and absorption can be reduced.

In addition, the effect of this light is 4LK on the conventional equipment VT.
This is obtained by providing a component 1) A New Year's filter, and its operation is the same as the conventional one.

In the present invention, the characteristics of νE can be greatly improved by simply adding a simple configuration to the conventional circuit.

[Brief explanation of drawings]

Figure 11. The 212th is an implementation of the base i'A IIiν-containing he-internal circuit according to the present invention (212).
Show each tari. In the figure, 1 is an input terminal, 2.4 is a 711" detector, 3 is a phase shifter, 5 and 9 are an exclusive 1st circuit, 6 is a 2nd circuit, and 7 is a 711" circuit. Range passing 1. Tight filter, 8 is a waveform converter, 10 is a loop filter, 11 is a voltage controlled oscillator,
12, 1.3 are high-pass filters.

Claims (1)

[Claims] A first phase detector for extracting the two-wave base portion of the output of the first phase detector from each output of the first phase detector and the twentieth phase detector having a phase difference of π/2 from each other. and taking the square value or absolute value of the output of the second phase detector;
means for converting a waveform of a multiplier value or an absolute 1 inch output; and a means for converting a waveform of a multiplier value or an absolute 1 inch output; and a second means for further outputting a double harmonic component of the output of the double harmonic component extracting means.
Either the combination of the second double wave component extraction means described in iJ, or the combination of the square value or 413 to 1 (2) output waveform conversion means and the second double wave component extraction means,
11i01 A reference carrier regeneration circuit characterized in that the reference carrier regeneration circuit is operated through a pass filter that blocks the coupling.