SU1133697A1 - Two-frequency voice-frequency receiver - Google Patents

Abstract

1. A TWO-FREQUENCY TONE SIGNAL RECEIVER, containing a series-connected matching unit and a pulse shaper, the first and second And elements, the first and second binary counters, and the first execution unit, so that, in order to increase the selectivity and interference, as well as ensuring the speed of changing the frequencies of the tones, are introduced in series the delay unit and the second execution unit, the first T-flip-flop and the prohibition unit, the inputs of which are interconnected and with the output pulse generator, serially connected tone reference frequency block and second T-flip-flop, as well as a frequency divider with a fixed division factor, 5IR element, first and second D-triggers, with the second output of the tone reference frequency block. The signals are connected to the input of a frequency divider with a fixed division factor, the code of which is connected to the counting inputs of the first and second binary counters, and the input unit of the reference frequencies of the tonal signals is connected to the first output of the first non-. Additional unit, the second output of which is connected to. the input of the delay unit, the input And the first D-flip-flop is connected to the input C of the second D-trigger and the output of the first T-flip-flop; the input C of the first D-trigger is connected to the input D of the second D-trigger and the inputs of the second T-flip-flop the first and second 13 triggers are interconnected, with the output of the inhibit unit and with the first input of the first execution unit, the main outputs of the first and second D triggers are connected to the first inputs of the first and second elements And, respectively, the inverse output of the first trigger i is connected with the second input of the second The element And, and the inverse of the second D-flip-flop is connected to the second input; The first element And, the inverse output of which is connected to the input Reset the first binary counter, the output of which is connected to the first input of the element OR, the output of which is connected to the second inputs of the first and second execution units, the inverse output of the second element And connected to & 9 СЬ 1 input Reset the second binary counter, the output of which is connected to the second input of the OR element, the second output of the delay unit is connected to the third input of the first execution unit. . 2. The receiver according to claim 1, wherein the tone reference frequency block contains a crystal oscillator, a frequency switching block connected in series with the first encoder and the first frequency divider with a variable division factor, as well as sequentially soy

Description

the second encoder and the second frequency divider with a variable division factor, the output of the crystal oscillator is connected to the inputs of the first frequency divider with a variable division factor and to the input of the second frequency divider with a variable division factor, the outputs of which are connected to the first and second inputs

3697

the KOMMyTaiyiH frequency block, respectively, while the output of the frequency switching unit is the first output of the tone reference frequency block, the output of the crystal oscillator is the second output of the tone frequency reference block whose input is the third input of the frequency switching unit.

one

The invention relates to communication technology and can be used in selective call equipment.

A two-frequency tone signal receiver is known, comprising a sequentially connected amplifier, a frequency separation unit and a frequency protection unit, the outputs of which through resonant amplifiers are connected to the outputs of a frequency separation unit, as well as two frequency channels, each of which contains a threshold unit, two series-connected inverters, delay unit and recording unit ij,

However, this receiver has a low speed of changing the frequencies of tonal signals and insufficient selectivity.

Closest to the invention is a dual-frequency receiver of tonal sigrals, containing successively connected matching block and pulse shaper, first and second And elements, first and second binary counters, and the first execution unit 2j.

However, in a two-frequency receiver of tonal signals with a limited range of frequencies of transmitted tones and a large nx number, the high selectivity and high noise immunity, as well as the high frequency of changing the frequencies of received tones, are not fully realized

 The purpose of the invention is to increase the selectivity and noise immunity5 as well as to ensure the speed of changing the frequencies of the tonal signals.

The goal is achieved by the fact that the first and second elements AND, the first and second binary counters and the first execution unit are entered in series with the delayed unit and the second performance unit, the first T-flip-flop into a dual-frequency tone signal receiver containing serially connected matching unit and pulse shaper. and a prohibition unit, the inputs of which are connected by a melody and with the output of the pulse former, a series of reference frequencies of the tonal signals and a second T-trigger, as well as a divider are connected in series frequencies with a fixed division factor, an OR element, the first and second B-flip-flops, the second output of the tone reference block is connected to the input of a frequency divider with a fixed division factor, the output of which is connected to the counting inputs of the first and second binary counters 5 the frequencies of the tones are connected to the first output of the first execution unit, the second output of which is connected to the input of the delay unit, the input D of the first B trigger, is connected to the input C of the second J) trigger and you ohm of the first T-flip-flop, input C of the first D-flip-flop is connected to the input I) of the second D-flip-flop and with the output of the second T-flip-flop, inputs P of the first and second D-triggers are connected to each other the first input of the first execution unit, the main outputs of the first and second D-triggers are connected to the first inputs of the first and second elements And respectively, the inverse output of the first, 1) trigger is connected to the second input of the second element I, and the inverse output of the second and a trngter is connected to the second input of the first element AND, and The output of which is connected to the input Reset the first binary counter, the output of which is connected to the first input of the OR element, the output of which is connected to the second inputs of the first and second execution units, the inverse output of the second element AND to the input Reset of the second binary counter, the output of which connected to the second input of the OR element, the second output of the delay block is connected to the third input of the first execution unit. In this case, the tone reference frequency block contains a quartz oscillator, a frequency switching block, a first encoder and a first frequency divider with a variable division factor, and a second encoder and a second frequency divider with a variable division factor connected in series, the output of the crystal oscillator is connected to the inputs of the first frequency divider with variable division factor and with the input of the second frequency divider with variable division factor, the outputs of which are connected to the first and the second inputs of the frequency switching unit, respectively, while the output of the frequency switching unit is with the first output of the tone reference frequency block, the output of the crystal oscillator is the second output of the tone reference frequency block whose input is from the third input of the switching block the structural electrical circuit of the proposed receiver. Dual-frequency receiver of tone signals contains matching unit driver 2 pulses, first 3 and second 4 elements AND, first binary counter 5, second binary counter 6, first executive block 7 first T-flip-flop 8, second T-flip-flop 9, first B-flip-flop 10 , second D trigger 11, prohibition block 12, delay block 13, second execution block 14, i-fflH element 15, divider 16 with a fixed division factor, block 17 of the reference frequencies of tonal signals containing the first divider 18 with a variable division factor J second divider 19 with change by the dividing coefficient, the first encoder 20, the second encoder 21, the crystal oscillator 22, the frequency switching unit 23. Dual-frequency receiver tone signals as follows. In the absence of a signal at the input of the blocking unit 1, there is no impulse sequence at the output of the imaging unit 2, unit 12 closes the first input of the first execution unit 7. At the inverse outputs of the first and second elements And 3 and 4 there is a voltage of the logical unit5, while the output of the element 15 is logical zero signal. At the second output of the first execution unit. 7, the voltage of the logical unit is present, which is fed to the input of block 17, while the block 23 connects the output of the first divider 18, in the encoder 20 of which the code of the first tone frequency is set, to the second T-flip-flop 9. The block 13 is in this state, wherein the second input of the second execution unit 14 is closed. When a matching parcel block 1 arrives at the input, square pulses with a frequency ij and a duty cycle equal to two appear at the output of shaper 2 at the output of generator 2, while block 12 opens the first input of the first execution unit 7. At the output of the first Ttrigger 8 Rectangular pulses appear at a frequency of i - 2 to - which are fed to the input D of the first D-flip-flop 10 and the input C of the second D-trigger 11, to the input D of the second T) -trigger 11 and the input C of the first B-trigger 10 rectangular pulses are received with a frequency IQ and a duty cycle equal to d mind, from the output of the second T-flip-flop 9, C of the inverse outputs of the first and second elements I 3 and 4, rectangular pulses with a frequency F / ii / f 04 o and a duty cycle equal to two, arrive at the Reset inputs of the first and second binary counters 5 and 6, respectively, where FQ is the cutoff frequency of identification, determined by the formula, fo io | K, where i is the pulse frequency from the output of divider 16; K is the coefficient of recalculation of the first and second binary counters 5 and 6. At the counting inputs of the first and second binary counters 5 and 6, pulses are received with a frequency of ± from divider 1. At F FQ, the output of the element OR 15 will generate pulses. block 7, from the second output of which a pulse is applied to block 13, and the voltage at the second output changes from the logical unit level to the logic zero level, while this block 23 disconnects the output of the divider 18 from the input of the second T-flip-flop 9 and connects the output of the second divider 19, in the encoder 21 a code of the second tone frequency is set, to the input of the second T-flip-flop 9. Block 13, after a time equal to or greater than the switching time n; the first and second dividers 18 and 19, opens the second input of the second execution unit 14 When the dual-frequency receiver arrives at the input The signal of the second tone frequency fg and the inverse outputs of the And 3 and 4 elements appear rectangular pulses with a frequency F lin-ioi /. When P at the output of the element OR 15, pulses appear, the second execution unit 14 is triggered. The unit 13 closes the second input of the second execution unit 14 and changes the state of the second output of the first execution unit 7 from the logic zero level to the voltage level of the logical unit . Block 23 opens the output of divider 18, in the encoder 20 of which the code of the first tone frequency is set, and closes the output of divider 19, in the encoder 21 of which the code of the second tone frequency is set. Block 13, irrespective of the time of the appearance of the second tone frequency parcel (where Spd and tnoc2 is the duration of the first and second tone frequencies), after the first tone frequency is sent, closes the second input of the second execution unit 14 and changes the voltage level at the second the output of the first execution unit 7 from the level of logical zero to the level of logical one. If the input of a dual-frequency receiver tonal signals received tones with frequencies f, -. - i.f .... . c "fii 6 2 01 where m is 2,3,4, etc., then on the inverse outputs of the first and second elements I 3 and 4 appear rectangular pulses, the half-period of the zero level which is filled with pulses with filling frequencies f a l shh f -jfj.i respectively, i.e. the counting time of the first and second binary counters 5 and 6 is sampled and the sampling interval is much less than the counting time t, therefore the pulse sequence at the output of the SHSh 15 element does not work. The proposed two-frequency reception-. The nickname of tonal signals has high selectivity and noise immunity, as well as high efficiency of changing the frequencies of received tones.

Claims (2)

1. TWO-FREQUENCY TONE SIGNAL RECEIVER containing consecutively matching matching unit and pulse generator, first and second AND elements, first and second binary counters and first executive unit, so that in order to increase selectivity and noise immunity As well as ensuring the efficiency of changing the frequency of tones, the first binary counter, a delay unit and a second execution unit, a first T-trigger and a prohibition unit, the inputs of which are connected between themselves and with the output of the pulse shaper, consecutively connected unit reference frequency tones signa · ^, fishing and a second T-flip-flop, and the frequency divider with a fixed division factor, an OR gate, the first and vtoroyD flip-flops, wherein the second output reference frequency block tones. signals is connected to the input of the frequency divider with a fixed division coefficient, the output of which is connected to the counting inputs of the first and second binary counters, and the input of the block of reference frequencies of tonal signals is connected to the first output of the first source. an additional unit, the second output of which is connected to. the input of the delay block, the input Ό of the first D-trigger is connected to the input C of the second Ό-trigger and to the output of the first T-trigger, the input C of the first ΐ-trigger is connected to the input D of the second D-trigger and to the output of the second T-trigger, inputs P the first and second D-flip-flops are interconnected, with the output of the prohibition block and with the first input of the first actuating unit, the main outputs of the first and second Ώ-flip-flops are connected with the first inputs of the first and second elements AND, accordingly, the inverse output of the first AND-flip-flop is connected to the second input second element And, and the inverse output of the second .D-trigger is connected to the second input of the first element And, the inverse output of which is connected to the Reset input, the output of which is connected to the first input of the OR element, the output of which is connected to the second inputs of the first and second actuator blocks, the inverse output of the second element And is connected to the input Reset chick, the output of which is connected to the second input of the element OR, the second output of the delay unit is connected to the third input of the first Executive unit. 2. The receiver by π. 1, characterized in that the reference frequency block of the tonal signals comprises a quartz oscillator, a frequency switching unit, a first encoder and a first frequency divider with a variable division coefficient connected in series, and also a second binary count-Chd ^ sequentially connected second encoder and a second frequency divider with a variable division coefficient, the output of a crystal oscillator is connected to the inputs of the first frequency divider with a variable division coefficient and with the input of a second frequency divider with a variable coefficient divisions, the outputs of which are connected to the first and second inputs of the frequency switching unit, respectively, while the output of the frequency switching unit is the first output of the reference frequency block of tonal signals, the output of the crystal oscillator is the second output of the reference frequency block of tonal signals, the input of which is the third input of the block switching frequencies.