RU2787976C1 - Transceiver apparatus of a homodyne radar - Google Patents

Abstract

FIELD: radio engineering.

SUBSTANCE: invention relates to the field of radio electronics, in particular, to short range location, and may be used as a functional radar unit for measuring ranges, velocities, and angular coordinates of vehicles and pedestrians (hereinafter, reflectors) in traffic control and accident prevention systems. Transceiver apparatus of a homodyne radar additionally comprises a pulse modulator and a power amplifier in the transmitting channel between one of the outputs of the power divider and the microwave output of the apparatus, as well as a homodyne filter in each receiving channel between the output of the mixer and the homodyne signal amplifier. The pulse modulator and the power amplifier are linked by pulse modulation mode and output power control circuits with the controller processor. The homodyne filter suppresses the spectral components of the mixer signal exceeding the cutoff frequency of the filter. The cutoff frequency of the filter is set to be lower than the pulse modulation frequency, but higher than the maximum frequency of the homodyne signal of the probing signal fragment, as calculated for reflectors with maximum set values of ranges and radial velocities.

EFFECT: interval of measured ranges of a homodyne radar expanded by alternately applying two modes of the probing signal: continuous mode (for near-range reflectors) and quasi-continuous pulse mode (for far-range reflectors).

1 cl, 1 dwg

Description

The field of technology. The proposed device relates to the field of radio electronics, in particular, short-range radar and can be used as a functional radar unit for measuring ranges, speeds and angular coordinates of vehicles and pedestrians (hereinafter referred to as reflectors) in traffic control and collision avoidance systems.

The level of technology. In recent decades, short-range radar systems (hereinafter referred to as radars) have been widely used both to monitor the situation on highways and in object security systems. Their main advantage is the ability to provide objective data on the coordinates and velocities of reflectors located in the field of view at any time of the day and in any weather conditions. Strict requirements for cost and weight and size characteristics have led to the widespread use of homodyne transceivers in these radars. The classic analogue of the invention is a homodyne-type continuous broadband radiation (FMCW) radar, when part of the emitted frequency-modulated (FM) probing signal (FS) is supplied as a heterodyne to the receiver mixer (see the Radar Handbook in 4 volumes, ed. Skolnik volume 3, sections 4.9-4.10). Radars of this type, using linear frequency modulation (chirp) of the ZS and digital processing of a homodyne signal, are widely used. An important quality of FMCW radars - the ability to control space at the minimum ranges of reflectors (near zone) - is accompanied by a disadvantage that is characteristic of all radar systems using a continuous emitted signal. This is a decrease in the sensitivity of receivers due to the effect of amplitude (AM) noise of the emitted signal, which inevitably enters the receiving path of the radar due to imperfect isolation of the receiving channels from the penetration of noise of the probing signal. This effect leads to a decrease in the potential and limitation of the maximum range of the radar "near zone". It is eliminated by applying a quasi-continuous pulse (SOI) FMiCW emitted signal generated by pulse modulation of the FMCW signal. Increasing the potential of these radars in the "far zone" is achieved by the fact that the emitted signal is modulated by pulses, and the reception of weak reflected signals is carried out in the time interval between radiation pulses, where there is no noise of the emitted signal. An example is US patent WO 2008048318 A2, which is also an analogue of the present invention. The advantage of this and other similar solutions - the ability to work in the "far zone" - is accompanied by an inevitable disadvantage for pulsed systems - the difficulty in receiving reflector signals - in the "near zone". The present invention solves the problem of expanding the interval of measured ranges of a homodyne radar by alternately using FMCW modes in a single device when operating in the near and, accordingly, FMiCW in the far zones of the measured ranges. The closest analogue and prototype of the present invention is an FMCW radar transceiver with correlation processing of a homodyne signal (article "Some possibilities of correlation processing of a homodyne radar signal with continuous frequency-modulated radiation", Izvestiya VUZ. Radiophysics, volume XLVIH, No. 10-11, 2005 , pp. 869-875, figure 2). The radar uses a continuous phase-modulated radiated signal and contains antenna-feeder (AFU) and transceiver (PPU) devices connected by microwave inputs and outputs. The PPU contains a source of a probing signal modulated by the processor in phase (hereinafter referred to as the FM signal generator) connected to the AFU and a receiving channel, including a mixer connected by inputs to the generator and the AFU output, and by the output through the homodyne signal amplifier (GS) to the processor. The processor controls the PPU parameters and calculates two-dimensional (range-speed) matrices of coefficients (functions) of correlation of the output digital homodyne signal of the transceiver and matrices of basic signals. By extreme values of the coefficients, it detects reflectors, and by the numbers of rows and columns of matrices it determines their ranges and speeds. Since the number of columns and rows of matrices, as well as the size of their elements, is not theoretically limited, the real limiting ranges and speeds of detected reflectors are determined by the technical parameters of the system, primarily by the parameters of the transceiver.

Disclosure of the essence of the invention. The aim of the invention is to create a transceiver device, which is an integral part of a homodyne radar (a hybrid of FMCW and FMiCW radars), capable of providing alternate use of two probing signal modes: continuous (for reflectors of the near range zone) and quasi-continuous pulsed (for the far zone). In the proposed invention, the task is to eliminate the above disadvantages of the prototype by additional use of the mode of pulse modulation of the emitted signal with the reception of the reflected signal of the far zone in the time intervals between radiation pulses. At the same time, by increasing the average radiated power, the potential of the radar can be increased, and the algorithms for digital processing of the received signal are preserved, since the transceiver device eliminates the pulse modulation of the homodyne signal at the stage of its analog processing.

The problem is solved by improving the transceiver of a homodyne radar containing transmitting and receiving channels connected by microwave output and inputs to the antenna-feeder device, and by digital inputs and outputs to the radar processor. In a transmission channel connected to the microwave output of the device, containing a source - a master generator of a microwave probing signal in the form of a sequence of phase-modulated fragments (hereinafter referred to as the PM signal generator), a processor-controller connected to the generator phase control input and to the radar processor, and a power divider, connected by the input to the output of the generator, and by one of the outputs to the microwave output of the device, according to the invention, an additional pulse modulator and a power amplifier are included, connected by control circuits for the pulse modulation mode and the output power level with the processor-controller. At the same time, in each receiving channel associated with one of the microwave inputs of the device, containing a mixer connected in series, connected by the input to the microwave input of the device and the corresponding output of the power divider, a homodyne signal amplifier and an analog-to-digital converter associated with the digital output of the device, is additionally included, according to the invention, between the mixer output and the homodyne signal amplifier there is a homodyne filter that suppresses the spectral components of the mixer output signal that exceed the filter cutoff frequency, which is set to a lower pulse modulation frequency, but greater than the maximum frequency of the fragment homodyne signal, calculated for reflectors with maximum specified ranges and radial speeds. As a result, the radar combines the ability to operate in the continuous (FMCW) mode of the emitted signal in the "near" and pulsed (FMiCW) - in the "far zone" while maintaining the shape of the output homodyne signal and its digital processing algorithms.

модулированных сигналом процессора-контроллера по фазе:Further, the main features of the invention are specified by mathematical analysis. The PM signal generator, controlled by the processor-controller, generates a probing signal (SS) in the form of a fragment or a sequence (package) of N fragments with durations

modulated by the signal of the processor-controller in phase:

- центральная частота зондирующего сигнала;

- задаваемый процессором-контроллером закон изменения фазы (модуляции) n-го фрагмента. Длительности

и законы модуляции фазы

фрагментов в пакете могут отличаться. Функция изменения частоты зондирующего сигнала (частотная модуляция) n-го фрагмента есть производная

а размах частоты фрагмента

- есть разность максимальной и минимальной частот ЗС, определяющий разрешающую способность радара по дальности. Фрагмент (1) усиленный и (при включении импульсного режима) модулированный импульсами по закону

(частота повторения импульсов -

скважность произвольна), излучается передающей антенной (номер фрагмента я далее для простоты опускается):where

- central frequency of the probing signal;

- the law of phase change (modulation) of the n-th fragment, set by the processor-controller. Duration

and phase modulation laws

fragments in the package may vary. The function of changing the frequency of the probing signal (frequency modulation) of the n-th fragment is the derivative

and the frequency range of the fragment

- there is a difference between the maximum and minimum frequencies of the ES, which determines the range resolution of the radar. Fragment (1) amplified and (when the pulse mode is turned on) modulated by pulses according to the law

(pulse repetition frequency -

the duty cycle is arbitrary), is emitted by the transmitting antenna (the fragment number i is omitted below for simplicity):

подается на гетеродинный вход микроволнового смесителяSignal (1) via attenuated power divider

applied to the heterodyne input of the microwave mixer

колебаний, модулированных по фазе

и амплитуде

с центральными частотами, изменившимися на величину допплеровского сдвига

Reflected from a plurality of reflectors and the received fragment signal is the sum of the time delays

phase modulated oscillations

and amplitude

with center frequencies changed by the amount of Doppler shift

- ЭДС сигналов «на клеммах» приемной антенн; L_k - дальность k-го отражателя;

- частота допплеровского сдвига принятого отраженного сигнала,

- радиальная скорость k-го отражателя. Принятые сигналы (3) и выходной сигнал ответвителя (1а) поступают на аналоговый активный элемент микроволнового смесителя (например полупроводниковый диод) генерирующий сигнал

описываемый произведением функций (1a) и (3). Отделив энергетические параметры

определяемые известным из уровня техники основным уравнением дальности радиолокации, получим из (3) нормированную функцию (4) сигнала фрагмента:where -

- EMF signals "at the terminals" of the receiving antennas; L _k - range of the k-th reflector;

is the frequency of the Doppler shift of the received reflected signal,

- radial velocity of the k-th reflector. The received signals (3) and the output signal of the coupler (1a) are fed to an analog active element of the microwave mixer (for example, a semiconductor diode) generating a signal

described by the product of functions (1a) and (3). Separating the energy parameters

determined by the basic radar range equation known from the prior art, we obtain from (3) the normalized function (4) of the fragment signal:

which is a pair of terms with the sum (5) and the difference (6) of the phases of the factors (4):

where

устанавливается существенно меньшей частоты повторения импульсов, но - для сохранения полезной информации - большей максимальной расчетной частоты гомодинного сигнала. При этом используется известный из уровня техники факт, что верхняя частота спектра сигнала (6) при гомодинном приеме возрастает с увеличением скорости и дальности отражателей и при заданной функции ФМ фрагмента легко рассчитывается. Согласно изобретению, импульсный сигнал (6) детектируется смесителем и гомодинным фильтром, а результат - нормированный, непрерывный, усиленный и ограниченный по частоте гомодинный сигнал n-ного фрагмента k-го отражателя, существующий в интервале времени

принимает вид (индексы k и n здесь и далее также опускаются):The task of the classical version of the heterodyne mixer is the generation and selection of oscillations with the input phase difference (6) and the suppression of the component (5) with the total frequency (phase) of the input signals. This function is implemented in various ways: using, for example, a low-pass filter, structurally integrated with the mixer. As a result of these operations, the beat signal or difference signal (6) retains both phase and pulse modulation. This option is used, as a rule, in analogues of the proposed solution. The disadvantage is the complication of digital signal processing (6). The present invention proposes a variant of amplitude demodulation of the pulse output signal (6) of the mixer, for which an additional homodyne filter (HF) is included between the mixer output and the amplifier input, which suppresses the upper frequency components of the signal (6) due to pulse modulation. To do this, the filter cutoff frequency

a significantly lower pulse repetition rate is set, but - to save useful information - a higher maximum calculated frequency of the homodyne signal. In this case, the fact known from the prior art is used that the upper frequency of the signal spectrum (6) with homodyne reception increases with increasing speed and range of the reflectors and is easily calculated for a given function of the FM fragment. According to the invention, the pulse signal (6) is detected by the mixer and the homodyne filter, and the result is a normalized, continuous, amplified and frequency-limited homodyne signal of the n-th fragment of the k-th reflector, existing in the time interval

takes the form (indices k and n are also omitted here and below):

- время задержки сигнала при максимальной заданной дальности отражателя, а

- длительность соответствующего фрагмента. Очевидно, что в идеале сигнал (7) не имеет импульсной модуляции, а переход приемо-передающего устройства радара от режима непрерывного зондирующего сигнала к квазинепрерывному (импульсному) осуществляется простым включением импульсного модулятора. Здесь не рассматриваются вопросы энергетики и другие особенности первичной обработки квазинепрерывных импульсных сигналов (в частности, защита входных цепей приемника), известные из уровня техники.Here

- signal delay time at the maximum specified range of the reflector, and

- duration of the corresponding fragment. It is obvious that, ideally, signal (7) does not have pulse modulation, and the transition of the radar transceiver from the mode of a continuous probing signal to a quasi-continuous (pulse) one is carried out by simply turning on the pulse modulator. It does not consider energy issues and other features of the primary processing of quasi-continuous pulse signals (in particular, the protection of the input circuits of the receiver), known from the prior art.

и широкополосного модуляционного (частота Δω_m((t.τ))=Δϕ_m(t.τ)/dt). Его удобно представить как сумму двух ортогональных составляющих cos[ω^Dt-Δϕ₀] и sin[ω^Dt-Δϕ₀], модулированных по амплитуде (DSB), соответственно, ортогональными сигналами cos[Δϕ_m(t.τ)] и sin[Δϕ_m(t.τ)]:The homodyne signal (7) of a fragment is a complex combination of two incoherent oscillations: a harmonic one with a Doppler shift frequency

and broadband modulation (frequency Δω _m ((t.τ))=Δϕ _m (t.τ)/dt). It is convenient to represent it as the sum of two orthogonal components cos[ω ^D t-Δϕ ₀ ] and sin[ω ^D t-Δϕ ₀ ], modulated in amplitude (DSB), respectively, by orthogonal signals cos[Δϕ _m (t.τ)] and sin[Δϕ _m (t.τ)]:

(для частного случая неподвижных отражателей ω_D=0) и две боковые полосы, сдвинутые (относительно ω^D) по частоте

Верхняя частота полезной области гомодинного сигнала

равна сумме максимальных частот: модуля частоты допплеровского сдвига

и модуляционной составляющей гомодинного сигнала

The spectrum of each term (7a) has a suppressed carrier with a frequency

(for the particular case of fixed reflectors ω _D =0) and two side bands shifted (relative to ω ^D ) in frequency

Upper frequency of the useful region of the homodyne signal

is equal to the sum of the maximum frequencies: Doppler shift frequency modulus

and the modulation component of the homodyne signal

и допустимой частотой повторения импульсов зондирующего сигнала

This value, which determines the requirements for the sampling frequency of the ADC, establishes in our case the ratio between the cutoff frequency of the homodyne filter

and allowable pulse repetition rate of the probing signal

Функция (спектр) выходного сигнала ППУ может быть уточнена вычислением свертки функций

и (7), или произведения спектра сигнала (7) на комплексный коэффициент передачи ГФ и УГЧ. Эта дополнительная операция, как и реализация разрешения отражателей по скорости, определяемая длительностью пакета фрагментов, решается в процессе цифровой обработки выходного сигнала ППУ процессором радиолокатора. Импульсная характеристика ГФ и УГЧ может использоваться для выполнения дополнительных операций аналоговой обработки гомодинного сигнала (например, его дифференцирования).The output signal of the device is a sequence of fragments (7) obtained by filtering with a homodyne filter and a homodyne signal amplifier having a total impulse response

The function (spectrum) of the PPU output signal can be refined by calculating the convolution of the functions

and (7), or the product of the signal spectrum (7) by the complex gain of the GF and UHF. This additional operation, as well as the implementation of the speed resolution of reflectors, determined by the duration of the packet of fragments, is solved in the process of digital processing of the PPU output signal by the radar processor. The impulse response of the GF and UHF can be used to perform additional operations of analog processing of a homodyne signal (for example, its differentiation).

The main version of the functional (structural) diagram of the transceiver is shown in the figure. The transmitting channel of the device contains a series-connected FM generator of the probing signal 1, a power divider 2, a pulse modulator 3 connected to one of the outputs of the power divider and capable of maintaining continuous radiation, and a power amplifier 4 connected to the PPU output and (through it) to the corresponding input of the antenna-feeder device of the radar. Each of the receiving channels of the device (a, b, etc.) is connected by its input to the corresponding output of the radar antenna-feeder device and contains mixers 5 (5a, 5b) connected in series, connected to the corresponding outputs of the power divider 2, a homodyne filter 6 ( 6a, 6b), a homodyne signal amplifier (UGS) 7 (7a, 7b) and an analog-to-digital converter (ADC) 8 (8a, 8b) associated with the radar processor. The processor-controller 9 is connected by analog or digital lines of communication and control of the parameters of the transmitting channel with the FM signal generator 1, the pulse modulator 3 and the power amplifier 4, and the PPU mode control input through the digital input-output with the radar processor. If the functions of the processor-controller 9 are supplemented, for example, by controlling the parameters of the UGS 7 or the homodyne filter 6, it is connected to them by additional circuits. The main variant of the block diagram ensures the operation of the PPU in the mode of a continuous emitted signal and the possibility of increasing the potential of the radar in the pulsed mode, as well as measuring the angular coordinate of the reflector by the phase difference of the signals in two receiving channels. It is possible, within the scope of the invention and known solutions from the prior art, to combine the functions of individual components of the device (for example, a power amplifier and a pulse modulator, a homodyne signal amplifier and a homodyne filter). It is also advisable to include input low-noise amplifiers in the receiving channels (either as a separate unit or as part of the AFU or PPU). At increased power levels of the emitted signal, the composition of the PPU can be supplemented by means of protecting the receiving channels known from the prior art (for example, power limiters or key devices). The signal generator 1 can be made, for example, according to the simplest scheme (oscillator controlled by the voltage of the ADC of the processor-controller), and by direct digital synthesis of the FM signal.

и функцию (1) модуляции фазы

и (в импульсном режиме) форму импульсной модуляции каждого (n-го) фрагмента зондирующего сигнала. Закон изменения фазы

может быть отрезком линейной, нелинейной (например, гармонической) или случайной функции. Он либо генерируется процессором радиолокатора, либо хранится в его базе данных. Выбор параметров КНИ режима (частота модуляции, форма импульса, скважность) в рамках указанного (9) ограничения определяется техническими требованиями к радиолокатору. При конструировании ППУ радиолокатора на основе выбора

фрагмента вычисляют модуляционную составляющую фазы Δϕ_m(t.τ_max)=ϕ_m(t)-ϕ_m(τ-τ_max), а также частоту модуляционной составляющей ГС

где

и определяют ее максимум

Сумма частот модуляционной и модуля допплеровской составляющих ГС

определяет максимальную полезную область спектра ГС и, следовательно, минимальную частоту среза гомодинного фильтра

Принципы способа корреляционной обработки гомодинного сигнала системы-прототипа позволяют регулировать в определенных пределах

и

каждого фрагмента путем выбора

и изменения размеров элементов основной матрицы базисных сигналов (ΔL, ΔV), оставляя неизменными (подбором размеров матрицы) заданные значения предельных дальностей и радиальных скоростей отражателей.Implementation of the invention. The operation of the device is implemented as follows. The processor-controller 9, according to the program of the radar processor or the operator's command, sets, based on the given values of the resolution in range and the maximum range of the reflectors, the duration

and function (1) of phase modulation

and (in the pulse mode) the shape of the pulse modulation of each (n-th) fragment of the probing signal. The law of phase change

can be a segment of a linear, non-linear (for example, harmonic) or random function. It is either generated by the radar processor or stored in its database. The choice of SOI mode parameters (modulation frequency, pulse shape, duty cycle) within the specified (9) limitation is determined by the technical requirements for the radar. When designing a PPU radar based on the choice

fragment calculate the modulation component of the phase Δϕ _m (t.τ _max )=ϕ _m (t)-ϕ _m (τ-τ _max ), as well as the frequency of the modulation component of the GS

where

and determine its maximum

The sum of the frequencies of the modulation and the module of the Doppler components of the HS

determines the maximum useful region of the HS spectrum and, consequently, the minimum cutoff frequency of the homodyne filter

The principles of the method of correlation processing of the homodyne signal of the prototype system allow you to adjust within certain limits

and

each fragment by selecting

and changing the dimensions of the elements of the main matrix of basic signals (ΔL, ΔV), leaving unchanged (by selecting the dimensions of the matrix) the specified values of the maximum ranges and radial velocities of the reflectors.

формируемый в передающем канале ППУ генератором 1, направляется на вход делителя мощности 2, который подает часть мощности ЗС на вход двухрежимного (импульсный или непрерывный выходной сигнал) модулятора 3. Сигналы управления режимом ППУ модулятор получает от процессора-контроллера ППУ 9, который изменяет соответственно режимы генератора ФМ 1, импульсного модулятора 3 и усилителя мощности 4. Импульсный (2) или непрерывный (1) сигнал с выхода модулятора 3 поступает на вход усилителя мощности 4. Выходной сигнал с выхода усилителя 4 ППУ, средняя мощность которого, управляемая процессором-контроллером, в импульсном режиме может быть больше, чем в непрерывном, подается на вход антенно-фидерного устройства (АФУ) и излучается в пространство. Принятые отраженные сигналы с выходов АФУ поступают на входы смесителей приемных каналов 5 ППУ. Поскольку число их, как правило больше единицы, они обозначены индексами (5а, 5b). Смесители получают на вторые входы непрерывный гетеродинный сигнал (1а) с соответствующих выходов делителя мощности 2 передающего канала. Из полученного в результате преобразования выходного колебания (6) смесителя 5 каждого канала гетеродинный фильтр 6, выделяет гомодинный сигнал (7, 7a). Частота среза

гомодинного фильтра должна соответствовать условиям (9) и (8), что гарантирует подавление лишних, превышающих

высокочастотных составляющих ГС. Он поступает далее на вход усилителя ГС 7, а с его выхода - на аналого-цифровой преобразователь 8. Процессор-контроллер 9 получает сигналы процессора радара и передает генератору ФМ, импульсному генератору, усилителю мощности команды на выбор режимов. АЦП 8 доставляют процессору радара выходные фрагменты ГС каналов в цифровом формате. Для реализации требуемых значений разрешения отражателей по скорости длительность одного фрагмента, как правило, недостаточна, процессор радара использует последовательность фрагментов.Probing continuous microwave signal of fragment (1), the phase of which is modulated according to the law

generated in the transmitting channel by the PPU by the generator 1, is sent to the input of the power divider 2, which supplies part of the power of the ES to the input of the dual-mode (pulse or continuous output signal) modulator 3. The modulator receives the PPU mode control signals from the PPU 9 processor-controller, which changes the modes accordingly FM generator 1, pulse modulator 3 and power amplifier 4. A pulse (2) or continuous (1) signal from the output of modulator 3 is fed to the input of power amplifier 4. The output signal from the output of amplifier 4 is the PPU, the average power of which, controlled by the processor-controller, in the pulsed mode, it can be more than in the continuous one, it is fed to the input of the antenna-feeder device (AFD) and radiated into space. The received reflected signals from the outputs of the AFU are fed to the inputs of the mixers of the receiving channels 5 PPU. Since their number is usually greater than one, they are designated by indices (5a, 5b). The mixers receive on the second inputs a continuous heterodyne signal (1a) from the corresponding outputs of the power divider 2 of the transmitting channel. From the resulting conversion of the output waveform (6) of the mixer 5 of each channel, the heterodyne filter 6 selects the homodyne signal (7, 7a). Cutoff frequency

of the homodyne filter must comply with conditions (9) and (8), which guarantees the suppression of excess values exceeding

high-frequency components of the HS. It goes further to the input of the amplifier GS 7, and from its output to the analog-to-digital converter 8. The processor-controller 9 receives signals from the radar processor and transmits commands to select modes to the FM generator, pulse generator, power amplifier. The ADC 8 delivers to the radar processor the output fragments of the GS channels in digital format. As a rule, the duration of one fragment is not sufficient to implement the required values of reflector resolution in terms of speed; the radar processor uses a sequence of fragments.

The technical solutions proposed by the present invention implement the first stage of matched filtering (optimal processing) of the reflected received signal in any radio frequency range, including submillimeter, in a PPU with a continuous and pulsed (SOI) emitted signal. The set of functional units of the PPU, shown in the figure, is the current version of the device, which in radars for various purposes provides measurement of range, speed and one angular coordinate of the reflector. The expansion of radar tasks may require an increase in the number of PPU nodes while maintaining structural solutions. Naturally, the proposed structure and algorithms of the PPU can also be applied in purely pulsed radars, if operation in the "near zone" is not provided.

Groups of transceivers can be part of complex radar systems. These are, for example, monopulse radars, MIMO radars, etc. At the same time, the functions of some PPU nodes, for example, the processor-controller, can be transferred to the radar nodes. The function of the output signals of the homodyne filters, and, consequently, the output signals of the PPA does not change significantly when switching from continuous to pulsed radiation, which is the object of the invention.

Claims (1)

A transceiver device of a homodyne radar, containing transmitting and receiving channels connected by a microwave output and inputs to the antenna-feeder device of the radar, and the transmitting channel connected to the microwave output of the device contains a master generator of a microwave probing signal in the form of a sequence of phase-modulated fragments of the probing signal (FM probing signal generator), a processor-controller connected to the phase control input of the probing signal FM generator and to the radar processor, and a power divider connected by the input to the output of the FM probing signal generator, and by one of the outputs to the microwave output of the device, each the receiving channel connected to one of the microwave inputs of the device contains a mixer connected in series with the microwave input of the device and the output of the power divider, a homodyne signal amplifier and an analog-to-digital converter connected with a digital output of the device connected to the processor of the radar, characterized in that the transmitting channel between one of the outputs of the power divider and the microwave output of the device includes an additional pulse modulator and a power amplifier connected by control circuits for the pulse modulation mode and the output power level with the processor-controller, and an additional homodyne filter is included in each receiving channel between the mixer output and the homodyne signal amplifier, which suppresses the spectral components of the mixer signal exceeding the filter cutoff frequency, which is set to a lower pulse modulation frequency, but greater than the maximum frequency of the homodyne signal of the probing signal fragment, calculated for reflectors with maximum given ranges and radial velocities.

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