SU1386981A1 - Descrete ortogonal function generator - Google Patents

Abstract

The invention relates to automation and computing and can be used to create generator equipment for multichannel communication systems. The aim of the invention is to expand the class of tasks by reducing the effective width of the spectrum of the generated signals. The discrete orthogonal functions generator contains a clock generator I, a Walsh function generation unit 2, a pulse shaper 3, a trigger 4, keys 5 and 6, an adder 7 and multipliers 8. The introduction of a pulse shaper, a trigger, adder keys and multipliers in the generator allows you to form functions characterized by a smaller number of blocks and, consequently, a smaller effective width of the spectrum. This increases the efficiency of using a given frequency range, which allows you to organize a larger number of channels in the communication system. 3 il. with s

Description

from 00

O5

with

00

15

20

The value is identically not equal to zero (by determining the set of points with a measure "on the whole frequency axis. To determine the spectrum, one can use the effective width of the spectrum, which is determined by

 (oVGco / We / p / G (co) / Ma

ОOffO

where G is the (co) -spectrum of the complex ogib

arbitrary signal. In the case of a phase-shift keying, the interval in the numerator diverges the expression (1) does not make sense. But that the main part of the energy of the manipulated signal is concentrated

between the first zero

the duration of the phase-shift key element), the infinite limits of the tegral in the numerator can be replaced.

As a result of integrating the field, the effective width of the spectrum of the complex envelope of the phase-shift keying signal with c blocks (block

Wu eff

N (At)

 (2, -1),

(2

or

The invention relates to automation and computing and can be used to create generator equipment for multichannel communication systems. ; The purpose of the invention is to expand the class of tasks to be solved by reducing the effective spectral width of the generated signals.

FIG. 1 shows the functional; on the generator circuit of discrete orthogonal functions; in fig. 2 - time diagrams of the generator when forming one of the functions of the orthogonal system; in fig. 3 - system of generated orthogonal functions for case 2 8.

The discrete orthogonal functions generator contains a clock generator 1, a Walsh function generating unit 2, a pulse shaper 3, a trigger 4, keys 5 i and 6, an adder 7 and a multiplier 8.

The generator works as follows.

The initial state of trigger 4 is one. The potentials from the direct and inverse I outputs of the trigger 4 are fed to the control input of the keys 5 and 6. Thus, the key 5 is open, and the key 6 is closed. Under the action of pulses from the output of the clock generator 1, the outputs of block 2 are formed by 25 Walsh functions. The functions from the 2nd output of block 2 (the functions are ordered by Walsh) through the public key 5 are fed to the input of the adder 7, and from its output to the inputs of the multipliers 8, where it is multiplied by the corresponding Walsh functions.

B moments of changing the sign of the Walsh function generated at the second output of block 2, the shaper of 3 pulses is triggered. The pulses from its output change the state of the trigger 4, and hence the state of the keys 5 and 6. The open key 5 or 6 corresponds to the zero operand at the output of the adder 7. Thus, the output of the adder 7 passes the signal either or from the second output of block 2. This signal is multiplied in multiplier 8 by the Walsh function.

FIG. 2 shows time diagrams illustrating the formation of the function F (5,, c): a is the output of the clock generator 1; b - the second output of block 2; 0 - output of block 2; (d) output of block 2, corresponding to 45 taking into account μ: the corresponding Walsh function Wai (5.6); d - key output 5; e - output of the adder 7; W - output of adder 7; h is the output of the corresponding multiplier 8, on which the function F (5.6) is formed.

It is known that with an increase in the number of zeros of the complex envelope of the phase-shifted signal, the spectrum of the complex envelope of the phase-shifted signal shifts to higher frequencies, i.e. the shift of that part of the spectrum in which the base and part of the signal energy is concentrated, since the spectrum of the phase-shifted sig30 is fundamentally

eff

 2 / 2ts-1 At V N

3

where N is the number of elements of the phase-mapped signal.

Consequently, the more blocks -, g phase-shift signal, the b

.

For the signals generated by the pre-generator, the number of blocks is two values

N - 7G OR C

and the value of the maximum effective rins of the spectrum of the signal included in

N-1-2 2

coz determined

50

expression (3). At the same time, the effective spectrum spectrum of all signals formulated by the generator is approximately equal, since

N 2

N + 2

Claims (1)

Invention Formula 55 The generator of discrete orthogon functions containing a clock gene and a Walsh function generation unit It is not identically equal to zero (by connecting the set of points with a measure of "zero on the whole frequency axis. To determine the spectrum shift, we can use the notion of the effective width of the spectrum W eff, which is determined by  (oVGco / We / p / G (co) / Ma, (1) ОOffO where G (co) is the spectrum of the complex rounding. arbitrary signal. In the case of a phase-shift keyed signal, the interval in the numerator diverges and expression (1) does not make sense. But, considering that the main part of the energy of the phase-shifted signal is concentrated between the first zero mi at- the duration of the phase-manipulated signal element), the infinite limits of the integral in the numerator can be replaced. As a result of the integration, the effective spectral width of the complex envelope of the phase-shift keyed signal with c-blocks is obtained (block — a sequence of identical elements) Wu eff N (At)  (2, -1), (2) the same elements) or dova correlation of identical elements) eff  2 / 2ts-1 At V N 3 where N is the number of elements of the phase-shift keyed signal. Consequently, the more blocks the phase-shift keyed signal has, the more . For the signals generated by the proposed generator, the number of blocks has two values N - 7G OR C in view of c: and the value of the maximum effective width of the spectrum of the signal entering the system, N-1-2 2 is determined according to in view of c: expression (3). In this case, the effective spectral width of all signals generated by the proposed generator is approximately the same, since N 2 N + 2 Invention Formula 55 A discrete orthogonal function generator containing a clock generator and a Walsh function generating unit, wherein the output of the clock generator is connected to the clock input of the Walsh function generating unit, characterized in that, in order to expand the class of solved problems by reducing the effective width of the spectrum of the generated signals, it is entered pulse generator, trigger, two keys, adder and 2 multipliers (2 is the number of generated functions), with the output of the second Walsh function (the stop is connected to the information input of the second key, pulse driver output is connected to the trigger trigger input, inverse and direct trigger outputs are connected to control inputs of the first and second keys, respectively, outputs of the first and second keys are connected to the inputs of the adder, output of the adder are connected to the first inputs of all multipliers, outputs of the shaping unit Walsh) function formation unit Walsh functions are connected to the second Walsh functions are connected to the input of the form inputs of the corresponding multipliers, the pulse equalizer with the information inputs of the multipliers are outputs the house of the first key, the output, and the functions of the generator of discrete orthogonal functions of the formation unit of the functions. The sha is connected to the information input of the second key, the pulse driver output is connected to the trigger input, the inverse and direct trigger outputs are connected to the control inputs of the first and second keys, respectively, the first and second switches are connected to the inputs of the adder, the output of the adder is connected to the first inputs all multipliers, formation block outputs walsh functions connected to second but ppppppppp Fi.2. J ats1.c) fj Oii (7, Q) af (S, a) F (, V) Fig.Z F {0.v) F (1, c) FM f {, zj F (b, d) L F (ge)