SU957167A2 - Device for measuring delay line group lag time - Google Patents

Description

(5) DEVICE FOR MEASURING GROUP TIME

one

The invention is intended for use in radio engineering and can be applied in radiolocation and communication technology where dispersion delay lines are widely used.

According to the main author. St. tf 517000 a device is known for measuring the group delay time of delay lines comprising a pulse measurement signal generator, the output of which is connected to the first inputs of the delay line under study and the delay measuring unit, the second input of which is connected to the input of the delayed radio pulse conversion blog, the output of which is connected to the second B ) ode the investigated delay line lj.

A disadvantage of the known device is the measurement error of the group lag time within the band of operating frequencies of the investigated delay line due to the presence of DELAY LINES.

non-uniformity of the amplitude-frequency characteristic (AFC) of the investigated delay line within this region.

The aim of the invention is to improve the accuracy of measurement of the group lag time.

This goal is achieved in that a device for automatic adjustment of the amplitude of delayed radio pulses, the input of which is connected to the output of the delay line f5 under study, and the output to the outputs of the delayed radio pulse spectrum and delay measurement units is inserted into the device for measuring 10 group delay times of delay lines.

FIG. 1 shows a block diagram of the proposed device; in FIG. 2 - timing charts of the device.

Claims (2)

The device contains a generator of 1 pulsed measuring signals, a source 9 2 tracked dispersion support line (DLD), a delay measurement unit 3, a delayed radio pulse spectrum conversion unit, and an automatic control unit 5 for the amplitude level of delayed radio pulses. The output of the generator 1 is connected to the unit 3 for measuring the delay and the input of the delay line 2. Its output through the block 5 is connected to the delay measurement block 3 and the conversion unit k. The second input of the delay line 2 under study is connected to the output of the spectrum converting unit. The device works as follows. The generator 1 generates radio pulses (Fig. 2a) arriving at the input of the investigated line 2 delay. A characteristic of the transformation of a delayed radio pulse is shown in FIG. 2B; The signals from the output of the delay line 1 (Fig. 26) are fed to blocks 3 and through block 5 of the automatic adjustment of the amplitude of the delayed radio pulses, which ensures the equalization of the amplitudes of responses over the entire bandwidth of its transmission. As a result, the same operating conditions of the converter A and the delay measurement unit 3 are ensured in the entire frequency range of the passband of the delay line 2, which reduces the readout error of the group delay due to the non-uniformity of the frequency response of the delay line 2 within its passband. performing conversion, in accordance with the characteristic (Fig. 2c.). After the secondary passage through its exit, a shortened twice-delayed radio pulse Chfig appears. 2d), in which the delay measurement unit 3 performs a group delay time reading (Fig. 2b) Thus, the use of an automatic adjustment unit in the proposed device significantly improves the measurement accuracy of the group delay time by eliminating the effect of non-uniformity of the frequency response of the delay line under investigation operating frequencies to the measurement results, since the measurement of the delay is made from the responses with the same amplitude. delaying delay lines according to aut. St. No. 517000, which is different from the fact that, in order to improve accuracy, a block for automatic adjustment of the amplitude of delayed radio pulses, the input of which is connected to the output of the delay line under study, is entered into it, and output g to the inputs of the delayed spectrum radio pulse and delay measurement. 11 SOURCES of information taken into account during examination 1. USSR author's certificate No. 517000, class G О F 10/0, 1976. fff. / but