SU1629871A1 - Optoelectronic modulation spectrometer - Google Patents

Abstract

The invention relates to optoelectronics and is intended to measure and record the spectral density of radio signals in radio astronomy. The purpose of the invention is to increase the number of recorded spectral samples per unit of time and simplify the spectrometer. The spectrometer contains a modulator 1, a spectral receiver 2, an acousto-optic spectrum analyzer 3, a photodetector 4 based on devices with charge coupling (FPSS), a generator 5 reversing clock pulses, a counter 6, a reference generator 7, a recording device 9. FPSS 4 is made in the form the accumulation section, output registers and output devices, while it contains the accumulation section generator and the output registers and output devices generator. Additionally introduced differential amplifier 8, the inputs connected to the output devices and the output to the recording device 9. 3 Il. cl

Description

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The invention relates to optoelectronics, is designed to measure and record the spectral power density of signals in radio astronomy and is an improvement to the device according to the author. No. 1290194.

The aim of the invention is to increase the number of recorded spectral samples per unit of time and simplify the design.

Fig. 1 is a block diagram of an optical electron spectrometer; Fig. 2 shows a detailed structural diagram and the connections of a photodetector on devices with charge coupling (FPSS), a generator of reversible clock pulses, and a differential amplifier; FIG. 3 shows timing diagrams explaining the operation of the spectrometer.

The optoelectronic spectrometer contains a modulator 1, the first input of which is the input of the device and connected to antenna A, connected to the output of the spectral receiver 2, which is connected to the electrical input of the acousto-optical spectrum analyzer 3, the optical output of which is connected to the FPSS 4 The output of the generator 5 reversing clock pulses is connected to the control input of the FPSS 4, the first input of the generator 5 is connected to the output of the counter 6, whose input, the second inputs of the modulator 1 and the generator 5 are connected to the output of the reference generator 7, the electrical output of FPZS 4 is connected to the input of the differential amplifier 8, the output of which is connected to the input of the recording device 9.

FPSZ 4 contains accumulation section (СН) 10, two output registers (ВР) 11 and 12, and two output devices (ВУ) 13 and 14. Electric control input СН 10 is connected to output of generator 15 of accumulation section, and control inputs of registers 11 and 12 and control inputs WU 13 and 14 are connected to the first and second outputs of the generator 16 output recorders and devices. The output of the VU 13 is connected to the direct input of the differential amplifier 8, and the input of the VU 14 to the inverted input of the amplifier 8. Accumulation section 10 contains one row of CCD cells.

The spectrometer works as follows.

From the receiving antenna A, a radio signal arrives at the spectrometer input, which, in accordance with the signal of the reference oscillator 7, is modulated by the modulator 1 with the period Tm TI - t-Ta (Fig. 3a). The spectral receiver 2 amplifies the modulated signal in the reception frequency band and converts the frequency range of the received signal into the frequency range of the acousto-optical spectrum analyzer 3. In the latter, the radio signal is converted into an optical signal and its spatial spectral decomposition. The output optical signal of the spectrum analyzer 3 is projected onto CH 10 (Fig. 3b) FPSS 4. In the illuminated elements of the photodetector, a charge is accumulated, which is proportional to the intensity of the incident light and the accumulation time of the FPSR. Each element of the CH corresponds to its spectral reading.

Before the initial time point to, the elements of CH are cleared; in counter 6, the number of synchronous accumulation cycles (n) is doubled (2p). At the moment to, a signal Si is applied to the input of the spectrometer and charge q accumulates in the SN during the first

0 TL modulation half-period With the arrival of a pulse from the reference generator 7 at the time ti, Si is switched to $ 2 with the help of modulator 1, generator 5 generates a pulse sequence that moves the charging terrain, which reflects the power spectrum Si of time averaged Ti HF in BP 11 (Fig. 3b), at the same time CH is cleared. At the same time moment ti by impulse with

0 of the reference generator 7, the contents of the counter 6 are reduced. Over a period of time Ta in the CH, a charge relief is formed, reflecting the spectrum of the signal For. On the next pulse from the reference generator 7 at the moment

5 times ta synchronously with the switching of the modulator 1, the generator 5 generates the reverse sequence of clock pulses, which transfers the accumulated charges to BP 12. At the same time, the counter 6 decreases its content. Such movement of charge packets from HF to BP 11 or BP 12 occurs until the number of synchronous accumulation cycles equals 5 given (n). At the moment of time to + nTM, the counter 6 generates a signal by which the generator 5 produces clock pulses producing output of the accumulated charge packets Q from BP 11 and 12 simultaneously, and the charges in BP 11 are accumulated during the time nTi, and BP 12 - during pTA. In WU 13 and 14, charge packets from the corresponding output registers are converted into a voltage signal and fed to

5 differential amplifier 8. The differential detected signal Uq from the output of amplifier 8 is recorded or displayed in a recording device 9 The maximum accumulation time of one frame is associated with the phenomenon of thermo-generation-recombination and can reach several hours at a substrate FPSS of 200 K.

The use of a differential amplifier and a FPZS with two BPI VU distinguishes this spectrometer from the known one, since by implementing the detection operation in analog form, the integral part of the majority of spectrometer elements is not needed, and the number of recorded spectral samples per unit time is increased by 10 times or at a given number of spectral channels reduces the integration time by a factor of 102.

Claims (1)

The invention of the Optical-electronic modulation spectrometer according to the authors. St. No. 1290194, characterized in that, in order to increase FIG. Z the number of recorded spectral samples per unit of time and simplified design, an additional differential amplifier was introduced into it, and a photodetector based on devices with charge coupling was made in the form of an accumulation section, two output registers connected to two output devices connected to the corresponding inputs 0 differential amplifier, the output of which is connected to the recording device, and two generators, while the electrical control input of the accumulation section is connected to the generator of the section 5 accumulation, the control inputs of the output registers are connected in parallel to the first one, and the control inputs of the output devices are connected to the second output of another generator. hh 1 Fi.Z tin ° Ј „- PI 0