SU1411986A2 - Device for testing radio receiver response to auxiliary reception channels - Google Patents

Abstract

The invention relates to a radio measuring technique. In order to increase the reliability of the control due to the control of the x-ki frequency selectivity by intermodulation of the 3rd and higher orders and measuring and recording the order of their components, serially connected 2nd amplitude comparator 6.2, el-8 and 3 are introduced key 1.3, information the output is connected to the output of the digital divider 7, and the output is connected to the auxiliary input of the recorder 9, the amplitude detector 14 connected in series, the input of which is connected to the auxiliary output of the radio receiver 25 being examined and the transmitter 19, the control input to which is connected with the 2nd output of the delay 18 elec-ta 18, successively connected by the Gr. 15 modulated signals (MS) and the matching unit 16, the 2nd input to which is connected (L

Description

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with the output 20 of the modulated signals (NMS), and the output of the block 16 is the input of the receiver 25, the NMS C 20 and the MS from r-15 through the block 16 are fed to the receiver 25, the frequency f of f-r-20 is set to the lower limit of the control range fJ . Frequency 15 set outside

bandwidth of the main receiving channel of the receiver 25; At the reference input of the comparator 6.1, a signal YJ, is set equal to the output signal of the receiver 25; when it rum, its sensitivity Xd is measured; At the initial moment the BS flip-flop 22 is in the initial state logical, zero 2 Il.

one

The invention relates to a radio-measuring technique, can be used to automatically control the susceptibility of radio receivers through side channels of reception with simultaneous automatic measurement and recording of frequencies — a harmonic signal from the generator and the heterodyne of the radio receiver, and is an improvement of the invention according to the author. No. 1264357.

The circuit of the invention is to increase the reliability of control by controlling the characteristic of the frequency selectivity by intermodulating three and higher orders and measuring and registering the order of their components.

Figure 1 shows the structural electrical circuit of the device proposed; on - the diagrams of the stresses, which give a hint to his work,

The device for monitoring the receptivity of radio receivers through side reception channels contains the first 1.1 second 1.2 and third 1.3 keys, the first 2.1 and second 2 0-2 phase de-tectors ;, the inverter 3, 4.1 and second 4.2 peak detectors, first

5.1 and second, 5.2 voltage transducers - code, first 6.1 and second

6.2 amplitude comparators, digital divider 7, element 8, recorder 9, adder 10, memory block 11, digital multiplier 12, counter 13, amplitude detector 14, oscillator 15 modulated signals, block 16 matching differentiating circuit 17e delay element 18 , expander 19, generator of 20 unmodulated signals, control unit 21, RS flip-flop 22, driver of starting pulses 23, driver of the reference signal 24, as well as radio receiver 25 under study,

The device works as follows.

The unmodulated signal Hz from the output of the generator 20 and the modulated signal from the output of the generator 15, equal to the specified rate X to the susceptibility levels of the studied radio receiver 25, are transmitted to the side 16 through the receive and intermodulation channels. the input of the radio receiver 25 under study, the frequency f of the generator of 20 unmodulated signals is set to the lower limit of the control range t and the frequency tf of the generator 15 of the modulated signals is outside the bandwidth of the main reception channel of the radio receiver 25 under test. YO is equal to the output signal of the radio receiver 25 under test, at which its sensitivity is measured. Xj.

At the initial moment, the RS flip-flop 22 is located in the initial state of the logic O, C of the driver 23 of the start pulses on the S-vhrd RS flip-flop 22 serves the voltage U (Fig. 2a), which translates it to the Log position, at the RS output -trigger 22 produces a voltage UO (Fig, 26), which by means of control unit 2 performs a smooth frequency tuning of the generator and 2p unmodulated) of signals in the frequency range. control f - f,

In case of dissatisfaction of the susceptibility levels of the studied radio receiver 25 through side reception channels of the specified rate X, if the frequency of the generator 20 coincides with the beginning of the start band of the first of these side reception channels, the signal Y is generated at the output of the radio reception 25. At the output of riepBoro amplitude comparator

6.1, a positive voltage uY O (Fig. 2c, t t) is generated, which opens the first 1.1 and second 1.2 keys. The oscillations of the signal generator 20 are fed to the counter 13 and the first phase detector 2.1, and the fluctuations of the intermediate frequency amplifier of the radio receiver under study 25 are fed to the second phase detector 2.2. When reaching the frequency of the generator signal

20 the upper limit of the passband of the first side channel of reception, the output signal Y of the studied radio receiver 25 becomes less than the reference signal YO, at the output of the first amplitude comparator 6.1, the voltage 4Y takes the value Log.O (fig.2b, tt) e and the first 1.1 and second 1.2 the keys are locked up. At. this at the outputs of the first 2.1 and second

The 2.2 phase detectors are produced with the voltage Uj and U. (FIG. 2d, d), the first of which, inverted by inverter 3, is remembered by the first peak detector 4.1 (FIG. 2e), and the second by the second peak detector 4.2 ( Fig.2zh). The rear edge of the pulse of the first amplitude comparator 6.1 is differentiated by a differentiating circuit 17, forming a positive pulse Uy (Fig. 2h), which, after a delay of time 7, in the element

18, the delay results of the counting of the counter 13 and the digital divider 7 are transmitted to the digital multiplier 12, where the harmonic frequency of the signal of the generator 20 is calculated, and the counter 13 returns to the initial state. The result of the multiplication f J. f p (fp -

the number of oscillations of the generator 20 of unmodulated signals during the time when the intermediate frequency of the studied radio receiver 25 is changed from the upper to the lower limit of its passband; n uj / i. - the ratio of the voltages produced by the first 2.1 and second 2.2 phase detectors) is transmitted for the second time by the delay element 18 delayed by time 2

adder 10, which receives the intermediate frequency fj from memory unit 11, and registrar 9. At the output of adder 10, the harmonic frequency of the heterodyne of the studied radio signal of type 25 ff + + fj is generated, which, like the harmonic frequency of the generator 20, is registered When the signal of the generator 20 falls into the bandwidth of the next reception channel, the level of susceptibility of the radio receiver 25 for which does not satisfy the specified rate, the measurement process is repeated. In this case, the differential pulse from the leading edge of the voltage and 4Y of the first amplitude comparator 6.1 converts the digital divider 7, digital multiplier 12 and adder 10 to the initial state.

In the case of passing through the output of the studied radio receiver 25 of the signal formed as a result of intermodulation of the third or higher order, the output of the first amplitude comparator 6.1 also generates a voltage of 4Y, at the outputs of the first 2.1 to the second 2.2 phase detectors - respectively, the voltage Uj and, which, as a result of the discrepancy between their flow values, form at the output of the second amplitude comparator 6.2 a positive voltage Ug (Fig. 2i), and at the output of the amplitude detector 14, the envelope mode is produced th e signal generator 15. The transformed vshr mntelem this envelope 19 in the form of a DC voltage Ug (FIG. 2k) is applied to the second input. element 8, to the first input of which is supplied the voltage U of the second amplitude comparator 6.2. Element I 8 triggers and at its output a voltage U ,, is generated (Fig. 2), which is fed to the controlled input of the third key 1.3. The third key 1.3 opens and the third input of the recorder 9 receives the numerical value n, which, as in the case of monitoring the susceptibility levels of the studied radio receiver 25 via side reception channels, is recorded by the recorder 9 simultaneously with the frequencies f (.. and f harmonics of the signal generator 20 and the local oscillator of the investigated radio 25.

: At THIS, the fixed value of | n 2 indicates the formation of the first intermodulation component of the third order, n 3 - the fourth order, etc.

; At the end of the control range at the frequency f from the output of the limit switch of the generator oscillator 20 of the aero-modulated signals, the R input of the flip-flop 22 is energized and returns to its original state: the Log.O stop, and the lacTOTbJ of the signal generator 20 are tuned and, therefore, monitoring and measurement is terminated.

 1 o rmula of invention

20 is not connected with the second output of the delay element, connected in series to a generator of modulated signals and a matching unit, the second input of which is connected to the generator output to a non-mode. No. 1264357, which is different from the fact that, in order to increase the reliability of the monitored signals, and the output of the block by controlling the matching characteristic is the input of the study of the frequency selectivity of the radio receiver.

 . -.

 Ag

modulating the third and higher orders and measuring and registering the order of its components, the second amplitude comparator connected in series, the first and second inputs of which are connected respectively to the outputs of the first and second peak detectors, the And and the third key elements, information the output of which is connected to the output of the digital separator, and the output is connected to the auxiliary input of the recorder, successively connected to an amplitude detector, the input of which is connected to the auxiliary output of the studied the receiver and the rectifier, the output of which is connected to the second input of the element I, and a control input connected to the second output of the delay element, serially connected generator of modulated signals and a matching unit, the second input of which is connected to the output of the generator of unmodulated signals, and the output of the block matching is the input of the radio being examined.

Claims (1)

Claim A device for controlling the susceptibility of radios through side channels of reception on autosw. No. 1264357, characterized in that, in order to increase the reliability of control by controlling the characteristics of frequency selectivity for intermodulation of the third and higher orders and measuring and recording the order of its components, 5 series-connected second amplitude comparator, the first and second inputs of which are connected respectively to the outputs of the first and second peak detectors, the And element and the third key, the information output of which is connected to the output of the digital divider, and the output is connected to an additional the recorder is connected in series with an amplitude detector 15, the input of which is connected to an additional output of the studied radio receiver, and a rectifier, the output of which is connected to the second input of the And element, and the control input is connected to the second output of the delay element, the modulated signal generator and the matching unit are connected in series, the second input of which is connected to the output of the generator of unmodulated signals, and the output of the matching unit is the input of the studied radio receiver.