SU930147A1 - Device for measuring frequency deviation - Google Patents

Description

 . one

This invention relates to radio measurements.

A device for measuring the frequency deviation is known, comprising output keys connected to the output of a counter, the input of which through a block of input keys is connected to the outputs of the register, a driver connected between the input of the device and the input of controlling the output keys, the reference generator whose output is connected to the inputs of the counter and the driver directly , and with the control output of the input key block via the delay element til.

However, such a device has an insufficient frequency range.

The closest in technical essence to the invention is a device comprising a series-connected matching unit, a driver, a key, two counters, the inputs of which are connected to the driver output and the generator output

frequencies, two additional keys, one of which is connected between the input of the first counter and the output of the reference frequency generator, and the second between the output of the first counter and the input of the third counter, the output of which is connected to the input of the readout unit, the other input of which is connected to the output of the second counter 2.

However, the known device does not

10 provides sufficient accuracy.

The purpose of the invention is to improve accuracy.

Claims (2)

The goal is achieved by the fact that a device containing a reference frequency generator15, two counters, the output of the first of which is connected to the control input of the first key, the second key and a gate generator, has four AND elements and a reversible counter, the inputs of which are connected to the outputs keys whose information inputs are respectively through the first and second elements And are connected to the input bus and the gate generator input, the control input of the second key is connected to the output of the second account snip, counter input, respectively through the third and the fourth and the elements connected to the outputs of the reference frequency generator, and the latter: the inputs of AND gates are connected in pairs to the output of the strobe pulses. .. The drawing shows a structural electrical circuit of the proposed device. The device contains And 1- elements, a gating pulse shaper 5, keys 6 and 7, a reference frequency generator 8, counters 9 and 10, and a reversing counter 11. The input signal is fed to the input bus 12. The principle of operation of the device is as follows. The signal under study is fed simultaneously to the inputs of elements 1, 2 and the driver 5, & where from the signal (e.g., using a frequency discriminator), the voltage of the modulating function is extracted, which is further converted into two sequences of gates. One of the gating pulse sequences is the inverted voltage of the other. These sequences come from the outputs of the imaging unit 5 and are supplied to the elements 1, 2, providing a partition of the signal into two sequences of radio pulses, each of which has its own frequency of filling. It is possible to determine the carrier frequency of each of the radio pulse sequences by counting the number of oscillations (naturally, during the period of existence of radio pulses, i.e., excluding the time intervals between them) per unit of time. Therefore, sequences of radio pulses are passed through keys 6, 7 for selected time intervals, which are formed as follows. The pulse generator 8 is passed to the counters 9, 10 in the time intervals affecting the elements 3, strobe pulses. The capacity of the counters 9 and 10 is selected from the condition of forming a given time interval T C-, where C is the capacity of the counter; T is the oscillation period of the reference frequency generator signal. Thus, the inputs of the reversible counter 11 receives two sequences of pulses in a given time interval, the difference of which is proportional to or equal to the frequency deviation during a time interval of one second. Improving the accuracy is provided by the possibility of performing sequentially parallel actions on the signal using serial elements of the analog-digital technique. Claims An apparatus for measuring frequency deviation, comprising a reference frequency generator, two counters, the output of the first of which is connected to the input. controlling the first key, the second key and the gating pulse shaper, characterized in that, in order to improve accuracy, four AND elements and a reversible counter, whose inputs are connected to the key outputs, are entered, the information inputs are connected through the first and second elements the input bus and the input of the gating pulse generator, the control input of the second key is connected to the output of the second counter, the inputs of the counters, respectively, through the third and fourth elements AND are connected to the outputs of the gene Rathore reference frequency, and the second inputs of AND gates are connected in pairs to the output of the strobe pulses. Sources of information taken into account in the examination 1. USSR author's certificate number, cl. G 01 R 23/00, 05.09.77. 2. USSR author's certificate No. 728089, cl. G 01 R 23/00, 07/05/77.