SU813799A1 - Device for synchronizing complex signals - Google Patents

Description

(54) DEVICE FOR SYNCHRONIZATION OF COMPLEX SIGNALS

one

The invention relates to telecommunications engineering and can be used to synchronize complex signals with frequency shift keying (FM) or frequency phase shift keying (hFM).

A device for synchronizing complex signals consisting of a serially connected mixer, a first bandpass filter, a first detector, a narrowband filter and a threshold element and serially connected copy copy generator, a discriminator, a filter, a controlled clock generator and a control unit is known, the first input of the mixer is connected with the signal input of the discriminator, the second input of the mixer is connected to the signal input of the signal copy generator, the output of the threshold element is connected to the input Lok control, a first output connected to a control input of the controlled oscillator, and a second output connected to a reset input of the narrowband filter tl.

However, such a device has a long synchronization occurrence.

The purpose of the invention is to reduce the time of entry into synchronism.

To achieve this goal, a device for synchronizing complex signals consisting of a serially connected mixer, a first bandpass filter, a first detector, a narrowband filter and a threshold power and series-connected signal copy generator, a discriminator, a filter controlled by such a generator and a block control, with the first mixer of the mixer connected to the signal input of the discriminator, the second input of the mixer connected to the signal output of the signal copy generator 5, the output threshold element connected to the input of the control unit, a first output connected to a control input of the controlled oscillator, and the second

0, the output is connected to the reset input of the narrow-band filter, the second band-pass filter connected in series, the second detector and the switch, the output of which is connected to

Claims (1)

5, the input of the threshold element, the output of the controlled clock generator is connected to the first controlled input of the switch; the second controlled input of the switch is connected to the third output of the control unit, and the input of the second: 0 band pass filter coincides with the input of the first band filter; scheme of the proposed device. The device for synchronization of complex signals contains mixer 1, first bandpass filter 2, first detector 3, uekopolane filter 4, co-mutator 5, threshold element 6, second band-pass filter 7, second teTKTOp 8, generator 9 copies of the signal discriminator 10, filter 11, a controlled clock generator 12, a control block 13. The device works as follows. At the first stage of the search by the commands of the control unit 13, the co amp & n mutator 5 is connected to the threshold element b, and the delay of the reference signal of the signal copy generator $ changes sequentially with a step equal to the duration of the elementary packet. At each delay value, the signal is checked by coherent accumulation in the first bandpass filter 2, detection, lateral accumulation in the narrowband filter 4, and comparison with the threshold Bandwidth of the first bandwidth filter 2 inversely proportional to the duration of the frequency response Af C5 the bandwidth of the narrowband filter 4 proportional to the time of analysis of the input sample at the first stage dP i T gKog. In this case, a narrowband filter 4 is polled and the accumulated voltage is reset in time and time, -fold. The value of TD is selected from the condition of reliable signal detection. When the threshold level is exceeded, the second stage of the search begins. At the same time, the second detector 8 is connected to the input of the threshold element b by the signal of the control unit 13 of the switch 5 and a successive change in the delay of the reference signal with a step equal to the width of the main peak of the autocorrelation function (ACF) at a level of 0.5 of its height. At each position of the reference signal, coherent accumulation occurs in the second band-pass filter 7, detection and comparison with a threshold level in threshold element 6. The bandwidth of the second band-pass filter 7 is selected from condition f, where is the time of analysis of one delay value at the second stage. When the input and reference signals coincide in time with an accuracy of the width of the main ACF peak, threshold element 6 is triggered and the search is stopped. Thus, the introduction of new elements significantly reduces the time of entry into synchronism. Apparatus of the Invention A device for synchronizing complex signals consisting of a series-connected mixer, a first band-pass filter, a first detector, a narrow-band filter and a threshold element and series-connected signal copy generator, a discriminator, a filter controlled by the Clock generator and a control unit, the first input of the mixer connected to the signal input of the discriminator, the second input of the mixer. connected to the signal output of the signal copy generator, the output of the threshold element The first output of the control unit is connected to the control input of the controlled clock generator, and the second output is connected to the reset input of the narrow-band filter, characterized in that, in order to reduce the synchronization time, the second band-pass filter the detector and the switch, the output of which is connected to the input of the threshold element, is connected to the first controlled input of the switch, the output of the controlled clock generator, the second controlled. the input of the switch is connected to the third output of the control unit, and the input of the second bandpass filter is connected to the input of the first bandpass filter. Sources of information taken into account in the examination 1. Hopkins P.M., I EEE Transaktfon on Communi Ca t i ons, 1977, Aug-ust, V. COM-25, N-8p 770 (prototype).