SU1412573A1 - Device for reinserting carrier - Google Patents

Description

(46) 06.23.91. Bul (and 23

(21) 4110698/09

(22) 06.23.86

(72) F.A. Pevzner and G.B. Hen

(53) 621.394.62 (088.8)

(56) D.Chakrabaty, C.J. Wolejeza

And IEEE journal of selected areas in communications, - vol. SAC-1, No. 1, January, 1983.

(54) DEVICE RECOVERY CARRIAGE

(57) The invention relates to telecommunications, can be used in demodulators of satellite communication systems and digital radio relay lines. The purpose of the invention is to improve the accuracy of carrier recovery while

simplify the device. The device contains a frequency mixer 1, a narrowband band-pass filter 3, a frequency divider 4, a phase detector 6, a low-pass filter 7, and an adjustable gr. 8. A frequency multiplying unit (BOOK) 2, a mixer 5 are inserted into the device, the BUCH 2 contains blocks of 9 times two. Reducing the frequency of the processed signal. Simplifies the implementation and configuration of the scheme. The number of blocks 9 multiplied by two is reduced by two times. The ability to select the frequency at which the x: ignition multiplication occurs allows to improve the noise immunity of the communication system. The phase dispersion of a particular oscillation and the number of carrier hops at the output of filter 3 increase with a decrease in the c / w ratio at the output of the BOOT 2. 1) w.

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with

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The invention relates to telecommunications and may be used in demodulators of satellite communication systems and digital radio relay lines.

The aim of the invention is to understand the accuracy of carrier recovery while simplifying the device.

The device contains the first frequency mixer 1, the frequency multiplying unit 2, the UEband band-pass filter 3, the frequency divider 4, the second mixer 5, the phase detector 6, the low-pass filter 7 and the adjustable oscillator AND 5 with the frequency multiplying unit 2 containing blocks 9 multiplying by two.

The device works as follows. .

The input phase-manipulated signal with the central frequency f and the harmonic signal of the generator with a frequency f not equal to f | arrive at the input of the second mixer .5, which jS transfers the spectrum of the phase-manipulator signal to the lower frequency region — the central frequency of the spectrum is equal to. .

noc eAyio3JitiM by multiplying into a block,., by multiplying frequency 2, phase ambiguity is removed from the phase-controlled signal, DOING phase multiplicity manipulation n 1,2,3, .., the number of phase values and 2 ,, For phase ambiguity c Such a 3S signal needs its frequency to be intelligent. to live on tons, for which you need 6 plots 9 times two. The frequency division of the frequency divider must also be made by t, In the particular case of a phase shift keyed signal. four phase, the number of blocks 9 multiplied by two equals two, and the frequency is divided into four.

The filtering of the restored non-4S and the second frequency transfer in the device is carried out in a known manner.

Thus, the device has the following sequence of 5; the number of blocks multiplied by two is halved, and instead of four

S

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S

., S

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two; reduction of the frequency of the processed signal; That signal simplifies the implementation and adjustment of the circuit; the ability to choose the purity at which the signal multiplies, improves the noise immunity of the communication system, due to the following considerations.

The phase dispersion of a particular oscillation and the number of carrier hops at the output of the narrowband bandpass filter 3 of the carrier recovery device increase with a decrease in the signal-to-noise ratio at the output of the frequency multiplying unit 2, therefore, as the noise multiplier of the frequency multiplier 2 increases, the noise immunity of the entire communication system decreases.

The noise factor of frequency multiplier 2 depends on the frequency of the signal being multiplied and, by choosing it, you can increase the noise immunity of the system.

Claims (1)

Invention Formula A carrier recovery device containing a series-connected narrowband bandpass filter, a frequency divider and a first frequency mixer, a serially connected phase detector, a low-pass filter and a tunable oscillator, the output of which is connected to the second input of the first frequency mixer, downstream to the output of the narrow-band band filter connected to the inputs of the phase detector, and the output of the first frequency mixer is the output of the device, different. so that, in order to increase the carrier recovery accuracy while simplifying the device, a second frequency mixer and iiacTo-irb multiplier unit, whose output is connected to the input of an adjustable bandwidth generator, are connected to the first input of the second frequency mixer, are introduced, The second input is the input of the device.