SU815662A1 - Device for measuring relative frequency deviation from nominal value - Google Patents

Description

one

The invention relates to a radio measuring technique and can be used in various communication devices when measuring parameters, information about which is presented in. form of frequency.

A device for measuring the relative frequency deviation from the nominal value is known, containing a reference oscillator, AND elements, counters, registers, control triggers, pulse drivers, delay lines, comparison circuits.

A disadvantage of the known device is the complexity of the implementation and the low measurement accuracy i.

The closest in technical essence to the present invention is a device comprising a control unit, a key generator, a measurement counter, a first measurement trigger, a cycle counter and a second measurement trigger 2.

A disadvantage of the known device is low measurement accuracy.

The purpose of the invention is to improve the measurement accuracy.

This goal is achieved in that a device for measuring the relative frequency deviation from the nominal value, comprising a control unit, serially connected pulse generator, a key, a measurement counter and the first measurement trigger, serially connected cycle counter and a second measurement trigger,

the second input of which is connected to the second input of the measurement counter, the second input of the first trigger and to the output of the control unit - the output of the second measurement trigger is connected to

the first input of the cycle counter and the second key input, and the second input of the cycle counter are connected to the first input of the control unit, a matching block is entered, the first trigger, the first AND, the OR and the variance counter, the second AND, and the second trigger, the output of which is connected to the second input

the control unit, the third input of the latter is connected to the output of the deviation counter, the fourth input of the control unit is connected to the output of the coincidence unit, the first input of which is connected

Claims (2)

with the first output of the first measurement trigger and with the first input of the first element I, the second input of which is connected to the key output, the first input of the second element I connected to the second output of the first measurement trigger, the second input of the second element I connected to the output of the generator | ImpulBsov, the third input of the second 1GO element AND is connected to the second output of the second measurement trigger, the second input of the OR element is connected to the third input of the measurement counter and to the output of the second And element, the second input of the second trigger is connected to the first input ervogo latch and output control unit, the second input of the first flip-flop connected to the output of the first AND gate and the output of the first flip-flop is coupled to a fifth input of the control unit. The drawing shows a diagram of the device. The device contains a pulse generator 1, a key 2, a counter of 3 measurements, a counter of 4 cycles, a trigger of 5 measurements, a trigger of cycle 6, a block of 7 coincidence, element 8 AND, element 9 AND, element 10 OR, trigger 11, trigger 12, counter 13 deviations and control unit 14. The device works as follows. If the frequency of the measured signal is less than the nominal value (F TO first fills the measurement counter 3, the output impulse of which throws the trigger 5 measurements and opens element 8 I. The reference frequency is transmitted via key 2, elements 8 AND and 10 OR enter counter 13 deviations When the counter of cycle 4 is filled, the trigger 6 of cycle is closed, closing key 2. The pulses in the deviation counter 13 are stopped. The transition of measurement trigger 5 and the trigger of cycle 6 to state 1 are recorded by the coincidence unit 7 as a signal End of measurement rhenium, received by block B of control unit 14. By this signal, the display of the deviation value is allowed. When the element 8 is output from the output of the first impulse And the trigger 12 is triggered, a deviation sign is registered (Fj (F). If the frequency of the measured signal exceeds the nominal value (FN), the cycle counter 4 is first filled and the cycle trigger 6 is activated, which closes key 2 and opens element 9 I (the cycle trigger worked, and the trigger 5 measured did not work yet). In this case, the reference frequency signal through the element 9 enters the counter 3 measurements (before filling it), as well as through the element 10 OR into the counter 13 deviations. At the same time, the first impulse from element 9 triggers trigger 11, registering a deflection error. When the measurement counter 3 is full, the measurement trigger 3 is activated by closing the element 9. The coincidence unit 7 records the end of the measurement. The magnitude and sign of the deviation is recorded by the deviation counter 13 and the control unit 14. At the end of a certain period of time generated by the control unit 14 necessary for indicating the measurement results, a Reset signal is generated again, and the measurement process is automatically repeated. Thus, the device registers a two-way frequency deviation from the nominal value and the sign of the deviation. If the measurement counter capacity is 100 times greater than the cycle counter capacity, the reference frequency F (quantization frequency) is 100 times higher than the nominal frequency, the measurement result is expressed as a relative deviation in percent. Accordingly, if the capacity of the measurement counter is 1000 times higher than the capacity of the cycle counter, and the reference frequency is respectively 1000 times higher than the nominal one, the measurement result is recorded with an accuracy of tenths of a percent, etc. If the frequency deviation of the measured signal is absent, then the cycle counter is excluded (measurement by a single pulse). If there is a frequency deviation or if there is no information about this parameter the counter, the loop performs the functions of an integration element. Thus, the proposed device allows direct recording of the percent two-way deviation of the measured frequency from the nominal value and allows to obtain any desired measurement accuracy. Apparatus of the Invention A device for measuring a relative frequency deviation from a nominal value, comprising a control unit, a serially connected pulse generator, a key measurement counter and a first measurement trigger, a serially connected cycle counter and a second measurement trigger, the second input of which is connected to the second input of the measurement counter, second input the first trigger and to the output of the control unit; the output of the second measurement trigger is connected to the first input of the loop counter and the second input of the key, and The loop counter input is connected to the first input of the control unit, carefully so that, in order to improve the measurement accuracy, a matching block, the first trigger, the successively connected first AND element, the OR element and the deviation counter are entered into it. , a second And element and a second trigger connected in series, the output of which is connected to the second input of the control unit, the third input of the latter is connected to the output of the deviation counter, the fourth input of the control unit is connected to the output of the coincidence unit, the first input of which is dinene with the first output of the first measurement trigger and with the first input of the first element I, the second input of which is connected to the key output, while the first input of the second element I is connected to the second output of the first measurement trigger, the second input of the second element I connected to the output of the pulse generator, the third input of the second element AND is connected to the second output of the second measurement trigger, the second input of the OR element is connected to the third input of the measurement counter and to the output of the second element AND, the second input of the second trigger is connected to the first input th first flip-flop and the output control unit, the second input of the first flip-flop connected to the output of the first AND gate and the output of the first flip-flop is coupled to a fifth input of the control unit. Sources of information taken into account in the examination 1. USSR author's certificate 535522, class G 01 R 23/10, 04,11.74. 2. USSR author's certificate number 344592, cl. H 03 K 29/00, 15.06.70.