SU902276A1 - Radio communication channel monitoring device - Google Patents

Description

(S) DEVICE FOR THE CONTROL OF A RADIO COMMUNICATION CHANNEL

The invention relates to a radio communication technique and can be used in devices for monitoring and selecting communication channels.

A device for monitoring a radio channel is known, comprising a series-connected noise generator, a switch and a radio signal receiver, the second input of which is connected to the first output of the control unit, the second and third outputs of which are connected respectively to the second input of the switch, to the third input of which a radio signal is applied, and the first input of the decision block 1.

However, the known device has a long time control.

The purpose of the invention is to reduce the control time.

For this purpose, a radio channel control device comprising a series connected noise generator, a switch and a receiver

the radio signal, the second input of which is connected to the first output of the control unit, the second and third outputs of which are connected respectively to the second input of the switch, the third input of which is supplied with a radio signal, and the first input of the decision unit, are connected in series with a logarithmic amplifier and analog-digital converter, the radio signal receiver is connected to the input of a logarithmic amplifier, and the second, third, fourth and fifth inputs of the decision block are connected to the fourth, second and first with the outputs of the control unit and with the output of the analog-digital converter.

Moreover, the decision block contains the first additional switch connected in series, the subtraction block, the second additional switch, and the memory block, the second input and output of which are connected respectively to the driver of the address code and the first input of the first additional switch, the second input of which combined with the second input of the additional switch, the output of which, the second and third inputs of the first additional switch, the input of the address code generator, and the second and third inputs of the subtractor are etstvenno output and the first ring WTO, third, fourth and fifth rows WMOs deciding unit. FIG. Figure 1 shows the structural electrical circuit of the device proposed; in fig. 2 is a variant in the decision block. The device for monitoring the radio channel contains a noise generator, switch 2, radio signal receiver 3, control unit k, logarithmic amplifier 5) analog-to-digital converter 6, decisive unit 7) which consists of (see Fig. 2, first and second) mutators 8 and 9, respectively, of block 10 of subtraction, memory block 11, shaper 12 of the address code and has five input buses 13-17 and one output bus 18. The device works as follows. The frequency range of the receiver is divided into five sub-bands, within which coeffie The receiver transmission agent can be considered constant. Before starting, the control unit switches the output 2 of the noise generator 1 to the input of the receiver 3 and switches the decisive block 7 into the calibration mode. After that, the control block 4 tunes the radio signal receiver 3 in all n subbands. the signal level of the noise generator 1 through the receiver and the logarithmic amplifier 5 enters the analog-to-digital converter (ADC) 6, where you convert it from analog to digital and enter the decisive block 7. In this block occurs subtraction of signal values supplied from the ADC, the value measured in advance at the minimum transmission ratio of the receiver noise signal generator 1, supplied from the control unit k, 6blok C is the minimum signal value is input in advance. of the transmitted signal and thus reduce the ADC size. In this case, the measurement results will be expressed in decibels. The code of the difference between the noise generator signal level measured at this frequency and the signal level of that generator measured at the frequency corresponding to the minimum transmission coefficient of receiver 3 corresponds to the increment of the transmission coefficient of receiver 3 at this frequency relative to the minimum. This code is stored in the decision block 7 at the address generated from the frequency code to which the receiver 3 is tuned to the control coming from block k. Thus, at the end of the calibration process in the decision block 7, the excess levels of the signals with respect to the minimum coefficient for this receiver, transmissions for all n subbands, will be stored. After that, the control unit through the switch 2 connects to the input of the receiver 3 an antenna and switches the decision unit to the measurement mode. In this mode, the control unit 4 tunes the radio signal receiver 3 according to the analyzed frequencies (channels). At the end of the analysis time of each frequency, on command c, the control unit k, the decision block 7 subtracts from the level of the measured signal arriving at it from the ADC corresponding to the given sub-band that the signal level exceeds the minimum level. Measurement results are output to the device. In one of the possible ways of building a digital decision unit (Fig. 2) in the calibration mode, a signal from the control unit, coming through the input bus 1b, the first switch 8 connects the input bus 13 to the subtraction unit 10 and disconnects the output of the memory unit 11 from Him, and The second switch 9 connects the output of the subtraction unit to the input of the memory unit 11 and disconnects it from the output bus 18. At the same time, the subtraction unit, taken from the control unit via the input bus 16, subtracts the signal level from the signal level. of 17 subband signal transferred via the input bus of the

generator, measured at the minimum receiver gain and coming from the control unit via the input bus It. The result of the subtraction is recorded via the second switch 9 into the memory block 11 at the address that is generated by the shaper 12 of the address code from the frequency code to which the receiver is configured, coming from the control unit over the input bus 15B in the measurement mode with the signal coming through the input bus 16, first switch 8 connects to block 10 the subtraction output of memory 11 and disconnects the input bus T from it, and the second switch 9 connects the output of the subtractor to output bus 18 and disconnects it from the input of memory 11. In this case, the subtraction unit 10, using a command received via the input bus 15, subtracts from the level of the measured signal input through the input bus 1, the amount of correction for the non-uniformity of the receiver transmission coefficient for a given subband coming from the memory unit 11. The address code of the memory unit is generated from the frequency code to which the receiver is tuned, which is fed in via the input bus 15 by the address code generator 12. The result of the subtraction goes through the second switch 9 to the output bus 18.

Thus, the proposed device is more reliable due to the fact that switching the input of receiver 3 from the antenna to the noise generator is performed only once before and after calibration, and the calibration itself is performed only when the device is initially turned on or after repair and maintenance work. reduces the channel analysis time by excluding the noise generator signal level and the receiver switching time from the antenna to the noise generator from the measurement time and vice versa.

Claims (2)

1. A device for monitoring a radio channel containing a noise generator connected in series, a switch and a radio signal receiver, the second input of which is connected to the first output of the control unit, the second and third outputs of which are connected respectively with the second input of the switch, on the third input of which a radio signal is applied, and with the first input of the decision block, characterized in that, in order to reduce time counter, introduced in series connected logarithmic amplifier and analog-to-digital converter, the output of the receiver of the radio signal is connected to the input of the logarithmic amplifier, and the second, the third, fourth, and fifth inputs of the decision block are connected respectively to the fourth, second, and first outputs of the control unit and to the output of the analog-digital converter. 2. The device according to claim 1,0 tons of liter, such that the decision block contains the first additional switch connected in series, the subtractor, the second additional switch, and the memory block, the second input and output of which are connected respectively to the address code generator and with the first entrance of the first Additional switch, the second input of which is combined with the second input of the additional switch, the output of which is the second and third inputs of the first additional switch, the input of the address code generator, and the second and third inputs of the subtraction unit are the output and the first, second, third, fourth and fifth inputs of the decision block, respectively. Information sources, taken into account in the examination 1. USSR author's certificate No. 720753, cl. H H 17/00, 1978 (prototype).