SU585619A2 - Device for synchronization with m-sequence - Google Patents

Description

one

The invention relates to radio engineering and can be used in communication systems with inverse modulation.

From the main auth. St. No. 347941, a synchronization device with a tn-sequence is known, which contains a block of element-wise, reception with a low-pass filter, a shift register with feedback, a multiplier switches, shift registers, a timing detection detector, a clock generator with a frequency divider and a threshold device. The output clock generator with a divider is connected in series to one of the switches, a shift shift register and one of the shift registers are connected to one input of the matches of the match adder. The element-wise reception unit is connected to the other inputs of the matches of the match adder. , the output of which through the threshold device is connected to one of the inputs of the control unit for entering into synchronism, the output of the multiplier is connected in series with the other of the switches and de Héctor determining synchro

the low is connected to another input of the synchromesh control unit, the output of which is connected to the switches.

However, this device is not sufficiently high accuracy of synchronism.

The purpose of the invention is to increase the reliability of the presence of

This is achieved by inserting a device into the device and subsequently connecting a reference time sensor, a code converter and an additional switch, with the output of an additional switch connected to the setup input of the shift register with feedback, and the control input of the additional switch of the switch. with the release of the synchronization acquisition control unit.

Synchronization device with irt-sequence). (Contains block 1 element-by-element with filter 2 low frequencies, register 3 shift with feedbacks, peramnoy gel 4, switches 5,6, registers

7.8 times, synchronization detection detector 9, clock generator 10 with frequency divider 11 and I threshold device 12.

8. the output of the generator 10 clock frequency with a divider 11 through serially connected one of the switches 6, the shift register 3 with reverse; communications and one of the shift registers 8 is connected to one input of bits of the adder; 13 matches. Unit 1 by element-wise reception through another of shift registers 7 is connected to other inputs of bits of adder 13 matches, the output of which through threshold device 12 is connected to one of the inputs of control unit 14 for entering synchronism. The output of the multiplier 4 is sequentially connected to the other one of the switches 5 and the detector 9 is determined to be synchronized to the other input of the synchrometer control unit 14, the output of which is connected to the switches 5, 6.

The device also contains a series-connected time reference sensor 15) a coding converter 16 and an additional switch 17, the output of the additional switch 17 is connected to the setup input of the feedback shift register 3, and the control input of the additional switch 17 is connected to the output of the control unit 14 synchronism,

Device 5p works as follows

The received TL-sequence signal passes through a low filter 2 often and is fed to a multiplier 4 and a unit-by-element block 1, which evaluates the signal at the receive rate and from which it is fed to the shift register 7 to sample the last received L, SYMBOLS fn - sequences.

With the arrival of the time stamp from the reference time sensor 15, taking into account the time code and the a priori known time delay, a code is formed on the code converter 16, which is formed successively in time fe of the phases of the local r-sequence, which are shifted to shift 8 register.

The number of k phases of the local sh-sequence, f is chosen based on the maximum; unstability of the reference sensor (15 time and -the accuracy of the time delay,

In adder 13, a one-by-one comparison is made, the received sample and the formed local sample, t, e, form a mutual correlation function, which is compared with the threshold in threshold device 12,

The enumeration process continues either until the threshold is exceeded or until the end of the enumeration of all k local samples. If the over-ride does not occur, a new sample is taken of the received Lee sequence, and then the process repeats with the arrival of a new one; timestamp.

After exceeding, the threshold 1 of the control unit 141 with the switch 5 switches the input of the synchronism detection detector 9 to the output of the multiplier 4, the forging input of the shift register 3 with the help of the additional switch 17 is disconnected from the output of the code converter 16, and the other input of the shift register 3 through the switch The transmitter 6 is connected to the output of the divider 11, and the formation of the local m-sequence is performed at the rate adopted. On multiplier 4, the symbols of the received and local sequences are multiplied. The result of the multiplication enters the synchronism detection detector 9, where a check is made for correctness of entering into synchronism for a sufficiently large interval of time.

The use of the proposed device increases the reliability of synchronism, since the choice of the frequency of the following timestamps: the possibility of working at the junction of inverted and non-inverted segments of the received PL-sequence is excluded.

invention formula

The synchronization device with the m-sequence according to autor. No. 347941, is different from the fact that, in order to increase the reliability of synchronism, serially connected reference time sensor, code converter and additional switch are introduced while the output of the additional switch is connected to the setup input a shift register with feedback, and the control input of the additional switch is connected to the output of the synchronization acquisition control unit.