RU2291467C2 - Super regenerative transceiver - Google Patents

Abstract

FIELD: the invention refers to radio technique particularly to radiolocation and may be used in upper-air radio sounds and meteorological rockets for measuring distance.

SUBSTANCE: the super regenerative transceiver has a generator of superior impulses, a master oscillator, a source of feeding and an antenna. At that there is introduced in it a diode and in series introduced a line out of a constant resistor, an alternate resister and a condenser. At that the input of the line is connected with the output of the generator of superior impulses, the output - with the input of the launching of the main oscillator, and the common point of the constant and the alternate resistors is connected with null volt of the source of feeding through directly switched diode, the generator of superior impulses and the main oscillator are connected with the plus and the null of the source of feeding, and the output of the main oscillator through antenna is the output of the super regenerative transceiver.

EFFECT: increases exploiting characteristics.

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Description

The invention relates to radio engineering, in particular to radar, and can be used in aerological radiosondes and meteorological rockets for measuring range.

A well-known super-regenerative transceiver with a separate generator of auxiliary oscillations, which serves to receive interrogation pulses and transmit response ones (see V.I. Ermakov and other "Atmospheric Sensing Systems", Gidrometeoizdat, 1977, p.247-249).

Its disadvantages are: large weight and size characteristics, the influence of the microwave field of the transmitter on the operation of the remaining nodes of the radiosonde, the presence of speed error in range.

Also known is a super-regenerative transceiver containing serially connected super-pulse generator, capacitor, self-oscillator, antenna, medium current stabilization unit, power supply with corresponding connections (see AS USSR No. 1106262).

Its disadvantages are a significant and unregulated shift of the reception frequency relative to the radiation frequency, which significantly reduces the operational parameters of the radio engineering system as a whole and does not allow full use of the potential of the super-regenerative transceiver, as well as low efficiency.

Known super-regenerative transceiver containing a generator of superimposing pulses, an oscillator, an antenna, a power source, a capacitor and an average current stabilization unit, an output of a generator of superimposing pulses through a capacitor is connected to the first input of the oscillator, an antenna is connected to the output of the oscillator, the first output of the power source is connected to the input of the generator pulses, the second output is with the input of the stabilization unit of the average current, the outputs of which are connected respectively to the second and third inputs an oscillator, wherein the oscillator is designed according to a two-resonator circuit and contains a transistor, first and second resonators, first and second chokes and inductance, the first resonator being connected between the inductance and the collector of the transistor, the second between the inductance and the emitter, the collector of the transistor is connected to the second input through the first inductor the oscillator, the emitter through the second inductor and the third input is connected to the common conclusions of the generator of the supercharging voltage, the stabilization unit of the average current and the power source, in the inductance is connected between the common point of the resonators and the base of the transistor, and the common point of the resonators and inductance is connected through the capacitor to the output of the generator of superimposing pulses, the antenna of the transceiver is connected to one of the terminals of the first resonator and is the input / output of the device, see RF Patent No. 2172965 - PROTOTYPE.

The disadvantage of the prototype (with all its positive advantages) is the connectedness of the adjustments in frequency and phase, i.e. if the frequency is regulated, then the phase is also regulated and vice versa, but in practice it is desirable and even necessary to have independent adjustments in frequency and phase.

An object of the invention is to improve performance.

To this end, it is proposed:

1. Superregenerative transceiver (SRPP) and its construct, containing a generator of superimposing pulses, a self-oscillator, a power source and an antenna, characterized in that it introduced a differential voltage regulator of the triggering pulses of the oscillator, consisting of a diode and a series-connected constant resistor circuit, a variable resistor and capacitor, and the input of the chain is connected to the output of the generator of superimposing pulses, the output is connected to the input of the start of the oscillator, and the common point is constant and variable of resistors through a directly connected diode is connected to zero volts of the power source, the generator of superimposing pulses and the oscillator are connected to the plus and zero of the power source, and the output of the oscillator through the antenna is the output of the SRPP.

2. The superregenerative transceiver and its construct according to claim 1, characterized in that the oscillator is made on a microwave transistor connected according to a scheme with a common base, and the oscillator mode is provided by the following elements and their inclusion: a power source through an RC filter and λ / 4 The MPL-choke (W3) is connected in series with the collector of the microwave transistor, which is also connected to the MPL-segment (W5), the second end of this MPL-segment (W5) is free, and approximately the middle of this MPL-segment (W5) is the output the oscillator and is connected to the antenna; the control input of the oscillator is connected: to the blocking capacitor and through λ / 4 MPL - the inductor (W1) - to the base of the microwave transistor and to the MPL segment (W4), the second end of which is free, the second end of the blocking capacitor is connected to the power supply zero; the emitter of the microwave transistor is connected through a λ / 4 MPL - inductor (W2) - to an interlock circuit consisting of a resistor and a capacitor connected in parallel, the second ends of which are connected to zero volts of the power source, while the emitter is connected to the MPL segment (W6), the second whose end is free.

3. The super-regenerative transceiver and its construct according to claim 1, characterized in that the electronic circuit construct is a common carrier board with a double-sided electromagnetic screen, on which a dielectric base made of highly stable dielectric material is placed, on the upper side of the dielectric base there is a self-oscillator on microstrip lines.

4. The super-regenerative transceiver and its construct according to claim 1, characterized in that its general construct is a microwave module circuit made in the form of a cylindrical body, inside of which is placed the construct according to claim 3, fixed to the base of the cylindrical screen with a screw and nuts, the screw passing through the middle of the carrier board and the dielectric sleeve, and the nut is placed outside the housing; the screw itself is made hollow inside with dielectric walls with a thread, to which an antenna with control elements is attached.

5. The super-regenerative transceiver and its construct according to claim 2, characterized in that the MPL segments of length <λ / 4 play the role of capacitance, and of length> λ / 4, they play the role of inductance, and the length of the segments is selected during adjustment depending on the values parasitic capacitances and inductances of the microwave transistor and the specific topology of the oscillator and its implementation, and initially the length of all the MPL segments is taken to be obviously longer than λ / 4, and during the tuning process it remains the same or cut off based on the conditions for obtaining the inductance or capacitance.

Figure 1 shows the electrical circuit of signal processing of GSI, figure 2 is an equivalent circuit of the oscillator of the proposed super regenerative transceiver (SRPP), figure 3 is an electrical diagram of the oscillator SRPP; figure 4 - the topology of the electrical circuit on the microstrip lines, figure 5 - constructive SRPP assembled in relation to the aerological radiosonde (ARZ), which depict: 1 - generator of superimposed pulses (GSI), 2 - signal processing circuit of the GPS, 3 - self-oscillator, R1 - current limiting resistor, R2 - variable resistor, D1 - differential diode, C1 - isolation capacitor, Le, Lk and Lb - stray capacitance of the emitter, collector and base of the transistor VT1, respectively, Sack - stray capacitance emitter collector, seb - pa nitric capacitance of the emitter base, SBC - parasitic capacitance of the base-collector, C2-C4 - tuning capacitors, W1-W3 - chokes λ / 4, W4-W6 - open MPL segments, R3 - protective resistor against inrush currents, C5 and C6 - blocking capacities, C7, C8 and R4 - filtering capacities and resistor from interference, 4 - ARZ case, 5 - screw, 6 - radio-electronic elements, 7, 8 - dielectric base and sleeve, respectively, 9 - nut, 10 - adjusting washer, 11 - antenna holder, 12 — antenna, 13 — MPL segment W6 in the emitter circuit, 14 — MPL segment W4 in the base circuit, 15 — capacitor C7, 16 — capacitor C8, 17 — resist p R4, 18 - microwave transistor VT1, 19 - capacitor C6 20 - resistor R3, 21 - the output microwave 22 - capacitor C5 23 - MPL-segment W5 in the collector circuit.

The super regenerative transceiver has the following connections.

In figure 1, the output of the generator of superimposing pulses 1 through a signal processing circuit 2 is connected to the control input of the AGZ, the output of which through the antenna A is the output of the SRPP, and the GSI 1 and AGZ are connected to the plus and zero of the power supply + U _pit .

Figure 3 shows the AGZ, which is made on a microwave transistor VT1 with the following connections: plus a power supply E _pit through a series connected λ / 4 inductor W3 and an RC filter on a resistor R4 and capacitors C7, C8 is connected to a collector VT1, which is also connected with the MPL segment W5, the second end of which is free, and approximately the middle of this segment is the AGZ output and connected to the antenna A of the radiosonde; the AGZ control input is connected to the blocking capacitor C5 and through λ / 4 the inductor W1 with the base VT1 and with the MPL segment W4, the second end of which is free, the second end of the capacitor C5 is connected to the power supply zero; the emitter VT1 is connected through a λ / 4 inductor W2 to a blocking circuit consisting of a resistor R3 and a capacitor C6 connected in parallel, the second ends of which are connected to zero volt of the power supply E _pit , while the emitter is connected to the MPL segment, the second end of which is free.

The indicated nodes of the circuit diagram can be performed on the following electro-radio elements: VT1 - microwave transistor type 2T975A (Powerful semiconductor devices, transistors. Handbook, edited by A.V. Golomedov, M, P and S, 1985, p. 503); capacitors C1-C8 leadless, type K 10-47 "B" (The reference book of the amateur radio designer, edited by PI Chistyakov, M, P and S, 1990, p. 403); microstrip lines (MPL), (Guide to elements of strip technology, under the editorship of A.L. Fildshtein, M, Communication, 1979, p. 20); resistors of the type P1-12 (The reference book of the amateur radio designer, edited by P.I. Chistyakov, M, P and S, 1990, p. 381); diode type KD116B-1 (Reference "Semiconductor devices, rectifying diodes", edited by A.V. Golomedov, M, KUBK-a, 1994, p. 89).

The tuning of the microwave oscillator (microwave-AGZ) is carried out on a standard laboratory bench with a wave impedance of 50 ohms. The necessary measuring devices are connected using a calibrated directional coupler (BUT). To simplify the final setup of the SRPP when working on the microwave-AGZ antenna, they are connected to a specific radio unit with which it is pre-configured. The voltage supply to the collector circuit VT1, measured directly between the output of the collector of the transistor and the common conductor (bus), should be in the range of 15-16 V.

The main output parameters that are controlled during the setup of the SRPP are:

1) radiation frequency SRPP;

2) output power;

3) sensitivity to the interrogation signal;

4) the combination of the frequencies of reception and radiation.

Essentially for the normal operation of the SRPP, it is necessary to select the lengths of the MPL W4, W5, W6, at which the optimum ratio of the active load and the feedback value in the microwave-AGZ is achieved, which are necessary for the superregenerative operation of the SRPP at the operating frequency. Additional adjustment of the time constant in the power supply circuit of the base of the microwave transistor VT1 provides the necessary stability of the SRPP in high sensitivity mode.

The operating frequency of the microwave-AGZ is determined by the length of the MPL W4, W5, W6. An increase in the length of any MPL leads to a monotonic decrease in the radiation frequency. However, a change in the length of any MPL simultaneously leads to a change in the magnitude of the feedback in the microwave oven and the active load. Therefore, the configuration process has an iterative nature. It is first necessary to establish the length of the resonators by cutting the adjustment pads according to the data obtained during the tests of the first control SRPP No. 1-5.

The magnitude of the microwave-AGZ load is determined by the connection point of the microwave output to the MPL in the collector circuit W6. The shift of the place where the microwave output is turned on to the open end of the MPL leads to an increase in the load of the microwave-AGZ and, as a rule, to an increase in the output power, a decrease in the sensitivity of the SRPP and vice versa. The most significant effect on the operation of the SRPP MPL W4, included in the base circuit, since it largely determines the amount of feedback in the microwave-AGZ. An increase in its length l under the condition l <λ / 4 leads to an increase in the feedback coefficient and an increase in sensitivity. MPL W6 in the emitter circuit affects the feedback value, the shift in the reception frequency relative to the radiation frequency.

The SRPP receiving frequency is determined by the parameters of the microwave transistor VT and the equivalent lengths of the resonators W4, W5, W6 and weakly depends on the supply voltage. The radiation frequency also depends on the amplitude of the pulse current of the collector of the microwave transistor VT. The larger the current amplitude, the lower the radiation frequency with respect to the reception frequency. Therefore, with an increase in the resistance of resistors R2 in the base circuit or R3 of the emitter circuit, the amplitude of the collector current decreases and the radiation frequency increases with respect to the reception frequency.

It is known that an increase in the capacitance of the capacitor C5 in the base circuit leads to an increase in the stability of the SRPP in the super-regenerative mode, but reduces the level of the secondary response. However, a decrease in the resistance value of resistors R2 in the base circuit and R3 in the emitter circuit increases the sensitivity of the SRPP. These dependencies can be used to adjust the combination of transmit and receive frequencies. It should be emphasized that in the coincidence mode of the reception and transmission frequencies, the SRPP works most stable under operating conditions, since there is no redundancy in the sensitivity of the device, which is obtained with a significant (more than 5 MHz) shift of the reception frequency relative to the radiation frequency.

When adjusting the SRPP, it should be remembered that the antenna of the radiosonde is galvanically connected to the base terminal of the microwave transistor VT1. Therefore, precautions against static electricity must be observed.

In the structural diagram of figure 1, the following assumptions are made: the general synchronization from the ALU or the microcontroller, which are also not shown, is shown, the antenna switch control is not shown, the internal structure of the receiver unit, etc., which are not mandatory, are shown directly work SRPP.

Phase adjustment, more precisely, the binding phase of the response signal to the phase of the interrogation occurs as follows (Fig. 1).

When pulses arrive from the GPS 1 through the signal processing circuit 2, the self-oscillator 3 starts up with a certain delay tset caused by noise oscillations and stray capacitances. If there is no request pulse, then for each pulse of the GSI 1 pulse AGZ have the form shown in Fig.6.

When the request pulse arrives during tset, the AGZ pulse will start from the request pulse, i.e. essentially will be a response (see Fig.7).

T.O. it can be seen that the phase of the response pulse is tightly connected with the arrival of the request pulse, i.e. with his phase. The arrival of interrogation pulses at any other time does not affect the start of the AGZ and therefore does not cause a response pulse correlated with the phase of the interrogation. The detection and processing of these signals (correlated or uncorrelated with the phase of the interrogation signal) is already the task of the ground-based radar.

In more detail, the work can be described as follows.

The principal feature of the SRPP is the complete statistical independence of the emitted radio pulses, i.e. the phase of each radio pulse, determined by noise fluctuations in the SRPP circuit at the time of its start, is completely uncorrelated with the phase of the previous radio pulse. Since the noise vibrations are close in nature to the "white noise", the initial phase of the radio pulses will be distributed evenly in the range from 0 to 2π. Therefore, the radio frequency emission spectrum of the SRPP is continuous, noise-like, broadband.

, что соответствует равномерному распределению фазы узкополосного стационарного нормального случайного процесса.When there is no signal at the input of the SRPP, the law of the density of the phase distribution of the random process, to which the phase distribution of the SRPP radio pulses obeys, is depicted as a straight line passing at the level

, which corresponds to a uniform phase distribution of a narrow-band stationary normal random process.

The appearance of a harmonic external signal in the SRPP loop with an amplitude comparable to and also exceeding the noise level leads to the appearance of a regular component in the phase distribution of the random process. In the general case, the phase distribution law of a random fluctuation process in a circuit when exposed to an external harmonic signal is described by an expression of the form:

provided | φ | ≤π,

where s = U _c / σ is the ratio of the signal amplitude to the rms value of the noise in the circuit;

F (scosφ) is the probability integral.

It can be clearly seen from the presented dependence that already at σ = 3 or more, the phase of the external signal is dominant and almost completely determines the phase distribution law. Thus, an external signal that is 10-15 dB higher in power than the internal noise in the SRPP loop causes almost complete synchronization of the phase of the SRP radio pulses. This ensures that the phase of the SRPP radio pulses is tightly coupled to the phase of the interrogation signal. In this case, the SRPP can be considered as a phase relay with a very high sensitivity. So, with real SRPP noise power in the range - 120-125 dB / W, the required power of the interrogation signal, providing phase synchronization, will be - 110-115 dB / W.

Thus, when a sequence of coherent interrogating radio pulses appears at the input of the SRPP, the SRPP corresponds to a sequence of synchronized coherent radio pulses, the spectrum of which has a discrete linear character.

The duration of the requested radio pulses τ _ss = 1.5-5 μs, which is several times greater than the duration of the radio pulses SRPP τ _and = 0.25-0.35 μs and ten times longer than the duration of the receiving interval τ _CR = 0.05 μs SRPP, during which the synchronization effect occurs. Thus, a coherent interrogation signal, due to phase synchronization from a continuous spectrum, forms a discrete, linear spectrum of SRPP. In this case, one of the discrete components of the spectrum is related to the frequency of the external signal ƒ _ss accurate to the phase, and the other discrete components will be located at a distance equal to the value of the supercharging frequency F _c , which is set by the generator of the superconducting voltage of the SRPP and from the external signal depends. In the general case, the position of the discrete components of the spectrum ƒ _{cnc i} relative to the carrier frequency ƒ _{cnc is} arbitrary and depends only on the current position of the frequency of the interrogation signal ƒ _ss relative to the carrier frequency of the SRPP ƒ _cnc .

The fundamental difference between the proposed method and the classical analogue is that the detection and processing of response coherent radio pulses occurs against the background of unsynchronized radio pulses, and the carrier frequency ƒ _SPP due to the instability of the microwave autogenerator SRPP can significantly differ from the frequency of the interrogated (probe) signal ƒ _зс in comparison with Doppler frequency shift. Therefore, to ensure the operability of the system under operating conditions, it is necessary to take measures to automatically adjust the frequency of the radar transmitter and receiver to the SRPP emission frequency, as well as to compare the phase of the interrogated and response radio pulses in order to detect and track the response signal in range against the background of unsynchronized radio pulses.

Claims (3)

1. Superregenerative transceiver (SRPP), containing a generator of superimposing pulses, a self-oscillator, a power source and an antenna, characterized in that a diode and a series-connected circuit of a constant resistor, a variable resistor and a capacitor are introduced into it, and the input of the chain is connected to the output of the generator of the generating pulses , the output is with the start-up input of the oscillator, and the common point of the constant and variable resistors is connected via a directly connected diode to the “zero” volt of the power source, the generator is driven and pulses and the oscillator are connected to the "plus" and "zero" of the power source, and the output of the oscillator through the antenna is the output SRPP. 2. The superregenerative transceiver according to claim 1, characterized in that the oscillator is made on a microwave transistor connected according to a scheme with a common base, and the oscillator mode is provided by the following elements and their inclusion: a power source through an RC filter and a λ / 4 MPL choke (W3) is connected in series with the collector of the microwave transistor, which is also connected to the MPL segment (W5), the second end of this MPL segment (W5) is free, and approximately the middle of this MPL segment (W5) is the output of the oscillator and is connected to antenna control input the generator is connected to the blocking capacitor and through the λ / 4 MPL inductor (W1) to the base of the microwave transistor and to the MPL segment (W4), the second end of which is free, the second end of the blocking capacitor is connected to the “zero” power source, emitter The microwave transistor is connected via a λ / 4 MPL choke (W2) to a blocking circuit consisting of a resistor and a capacitor connected in parallel, the second ends of which are connected to the “zero” volt of the power source, while the emitter is connected to the MPL segment (W6), the second whose end is free. 3. The super-regenerative transceiver according to claim 2, characterized in that the MPL segments of length less than λ / 4 play the role of capacitance, and the length of more than λ / 4 play the role of inductance, and the length of the segments is selected when tuning depending on the values of stray capacitances and microwave inductances -transistor and the specific topology of the oscillator and its implementation, and initially the length of all the MPL segments is taken to be obviously greater than λ / 4, and during the tuning process it remains the same or cut off based on the conditions for obtaining the inductance or capacitance.

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