RU2529177C1 - System for radio probing atmosphere with packet transmission of meteorological information - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: system comprises an aerological radiosonde (ARS) and a base station, which is a radar station, wherein the ARS includes a unit for preflight preparation of the ARS, which consists of a preflight preparation panel and an ARS parameter monitoring and recording unit, wherein the preflight preparation panel is connected through the ARS parameter monitoring and recording unit by a bidirectional bus M1 to the inputs of an ARS microcontroller; the radar station includes packet remote information decoding unit and a unit for secondary processing of the remote information and outputting atmospheric meteorological parameter signals, wherein the unidirectional bus M2 of the transceiving device of the radar station is connected through the packet remote information decoding unit to the unit for secondary processing of the remote information and outputting atmospheric meteorological parameter signals, the output of which is the output of the system.

EFFECT: high reliability of receiving telemetric information transmitted from an ARS to a ground-based radar station, high accuracy of measuring information transmitted from an ARS to a ground-based radar station, obtaining additional characteristics of measured atmospheric parameters.

3 cl, 4 dwg

Description

The invention relates to radio engineering and can be used in the modernization and development of new radiosonde (CP) systems with accelerated transmission of telemetric information from an aerological radiosonde (ARZ) to a ground-based radar station.

A common problem in the design and operation of CP is the creation of high-precision ARZ coordinate measurement systems for low-cost ARZ constructs that provide measurement with minimal error of atmospheric meteorological parameters (MPA), reliable transmission of telemetry information from the ARZ to a ground-based radar within the operational radius of the AR3-radar system. An independent problem in the creation and operation of CP is to ensure reliable and accurate transmission of telemetry information about MPA from the ARZ to the radar in conditions of fading of the radiosonde signal due to its swinging and uneven antenna pattern.

Domestic atmospheric radiosounding (CP) systems are constructed using the goniometric-ranging method of measuring coordinates, velocity and direction of movement of a radiosonde in a free atmosphere. The measurement of angular coordinates: azimuth (β), elevation angle (ε), as well as slant range (R _n ) is carried out by a radio-pulse method with an active response. Especially effective was the use of super-regenerative transceiver-transponders (SPP) as part of radiosondes. Intensive SPP radiation provides reliable transmission of telemetric information and tracking along angular coordinates. The high sensitivity of the SPP to the radio pulse interrogation signal makes it possible to generate a range response signal in the form of a short pause in the radiation of the interferometer with a reduced transmitter power of the interrogation radar pulses. Ultimately, it is very important that the coordinate determination system and the telemetry information transmission channel of the radio sounding system operate at the same carrier frequency (see V.I. Ermakov et al. "Atmospheric sounding systems", Gidrometeoizdat, 1977, p. 247- 249).

Known radio sounding system of the atmosphere of the radar type "Meteorite-RKZ", operating in the frequency range 1780 MHz (see Ermakov V.I., Kuzenkov A.F., Yurmanov V.A. Atmospheric sounding systems. - L .: Gidrometeoizdat, 1977. 304 s.). The RKZ-type tube radio probe is equipped with a super-regenerative transceiver (SPP), which, together with the ground-based Meteorite radar, provides measurement of angular coordinates, oblique range from the requested radio pulse and transmission of meteorological information to the radar, which is carried out by amplitude manipulation of the SPP radiation by a telemetric signal. The merit of the “Meteorite-RKZ” type CP is its complete autonomy, low cost of measuring MPA in the operational radius of action of up to 250 km.

The disadvantages of the system are the low noise immunity of CP during amplitude modulation of the SPP radiation by a telemetric signal, the long transmission interval of the meteorological information cycle (telemetry frequency cycle of the ARZ measuring transducer) for 20 seconds, which reduces the reliability and accuracy of MPA measurements under conditions of freezing of the ARZ signal when it sways.

A well-known radio sounding system for the atmosphere of the radar type AVK-MRZ operating in the range of 1780 MHz (Efimov A.A. Principles of operation of the aerological information and computer complex AVK-1. - M.: Gidrometeoizdat, 1989. 149 p.; Zaitseva N.A. Aerology. Gidrometeoizdat. 1990, 325 p.). The semiconductor ARZ type MP3-3 is equipped with a super-regenerative transceiver (SPP), which, together with the ground-based AVK-1 radar, provides the measurement of angular coordinates, the determination of the slant range by the requested radio pulse and the transmission of meteorological information to the radar, which is carried out by modulating the subcarrier (superimposing) frequency of the SPP telemetric signal. Advantages of CP type AVK-MRZ are full autonomy, low cost of measuring MPA in the operational radius of up to 250 km.

The disadvantages of the system for all its advantages are significant power consumption, as well as a large transmission interval of the meteorological information cycle (telemetry frequency cycle of the ARZ measuring transducer) for 20 seconds, which reduces the reliability and accuracy of MPA measurement, violates the stability of the ARZ signal auto-tracking in angular coordinates, and makes it difficult receiving and processing a telemetry signal at large duty cycles.

Known for the same type of small-sized semiconductor radar MARL and "Vector-M", which together with the ARZ type MP3-3 provide the measurement of angular coordinates, the determination of the slant range by the requested radio pulse and the transmission of meteorological information to the radar, which is carried out by modulating the subcarrier (superimposing) frequency of the SPP telemetry a signal (see Ivanov V.E., Fridzon MB, Yesyak S.P. Radio sounding of the atmosphere. Technical and metrological aspects of the development and use of radiosonde measuring tools. .. V.E.Ivanova Ekaterinburg, Ural Branch of Russian Academy of Sciences 2004. 596 with ISBN 5-7691-1513-0)... The advantages of the MARL-MRZ, Vector-M and MRZ type CPs are low power consumption, high automation of complex management and information processing, full autonomy, low cost of measuring MPA in the operational range of CP (up to 250 km) - PROTOTYPE.

The disadvantage of all systems and PROTOTYPE, with all their advantages, is the large transmission interval of the meteorological information cycle (telemetry frequency cycle of the ARZ measuring transducer) for 20 seconds, which reduces the reliability and accuracy of MPA measurements, violates the stability of ARZ signal auto-tracking in angular coordinates, and makes reception and processing difficult telemetry signal for large duty cycles. When the radiosonde sways due to the irregularity of its radiation pattern at the output of the radar receiver, at large distances, the signal fades to 10-20 dB with a period of 2-5 seconds. At the same time, the reception of the telemetric information of the radar is terminated, since the period of one cycle of transmission of the telemetric information of the radiosonde is 20 seconds.

The work of well-known CP is as follows. Domestic CPs that are in operation on the aerological network of Roshydromet radar type AVK-1, MARL, Vector-M, operate in conjunction with type MP3 radiosondes. The telemetry information in the ARZ is formed in the form of video pulses of a secondary measuring transducer (measuring generator), to which the resistances of the reference (calibration) resistor, temperature sensor and humidity sensor are connected in series. ARP transmits the IPA during one cycle, whose duration is T _p = 20 sec 2. During this time interval, the channel frequencies are transmitted sequentially for 5 seconds: the frequency of the reference (calibration) channel with a period T _op = 0.7 ms and the frequencies of the telemetric (measuring) channels of temperature and humidity, the periods of which vary depending on the state of the sensors within T _t = 0.8-60.0 ms, T _u = 0.8-10.0 ms. The frequency transmission of each channel occurs within 5 seconds. Information about MPA is contained in the Y-parameter, equal to the ratio of the period of the reference frequency T _op respectively to the periods of telemetric frequencies T _t , T _u :

$$Y_t=T_{\mathrm{about}P}/T_t;{\text{Y}}_{\text{u}}=T_{\mathrm{about}P}/T_u.\text{(one)}$$

Processing and issuing of meteorological information is carried out in a ground-based radar computer by calculating temperature and humidity from the values of the received periods T_op, T_t, T_u, known calibration coefficients of the ARZ measuring transducer and sensors with a cycle of 20 sec. With this method of transmitting telemetric information, the following problems arise:

- a large time interval for obtaining meteorological information (20 sec) creates the problem of its stable reception during signal fading at large distances of the radiosonde, since the signal fading interval is usually about 2-5 seconds. The appearance of at least one signal fading in the cycle (within 20 seconds) of information transfer does not allow calculating the Y-parameters and obtaining the measurement result;

- another problem arises when the frequency of telemetric signals caused by spurious amplitude modulation of the radiation of the ARZ transmitter falls into the passband of the radar automation channel of the radar and the stability of the ARZ auto-tracking along angular coordinates is violated;

- the third problem is associated with restrictions in existing CPs on the maximum period of the telemetric frequencies of the ARZ measuring transducer (IP), equal to T _tel.max = 60.0 ms. The period of the telemetric frequencies of the SP is determined by the resistance of the corresponding ARZ sensor. This limitation does not allow the use of modern temperature sensors with a small time constant based on bead thermistors with high resistance (of the order of 2-4 MΩ) at low temperatures of the order of minus 80-90 ° C, because the period of telemetric frequencies in this case, the IP significantly exceeds the permissible value of T _tel.max = 60.0 ms and the ground radar is not processed;

- additional difficulties arise when receiving a pulsed telemetric signal in the radar receiver when the period of video pulses changes within a significant range of T _bodies = 1.5-60.0 ms, since their duty cycle is changed, the constant component of the signal is tens of times, which complicates the operation of the threshold device of the meter pulse period.

The technical result of the proposed solution is:

- improving the reliability of receiving telemetric information transmitted from the aircraft to the ground radar;

- improving the accuracy of measuring coordinate-telemetric information (CTI) transmitted from the aircraft to the ground radar;

- obtaining new characteristics of the measured atmospheric parameters, for example, atmospheric turbulence;

- a significant reduction in the transmission time of MPA.

To solve this problem, an atmosphere radio sounding system with packet data transmission is proposed, which contains an aerological radiosonde — ARZ and a base station — a radar, a pre-flight pre-flight training unit consisting of a pre-flight training console and an ARZ parameters monitoring and recording unit with the following connections: the control unit and recording parameters ARZ connected bi-directional bus M1 with the inputs of the microcontroller ARZ; a radar unit for decoding packet teleinformation and a unit for secondary processing of teleinformation and issuing signals of atmospheric meteorological parameters with the following connections were introduced: a unidirectional bus M2 of a transceiver radar unit is connected via a decoding unit for packet teleinformation with a unit for secondary processing of teleinformation and issuing atmospheric meteorological parameters, the output of which is the output systems; the preflight preparation unit is made by a separate construct and connected to the upper-air radio probe for the time of entering the packet information format; it can also be decided programmatically in the ARZ microcontroller at the request of the customer; the upper-air radiosonde transceiver is designed according to a super-regenerator circuit and includes serially connected: a generator and a super-voltage modulator, an auto-bias circuit and a microwave oscillator loaded on the antenna.

Figure 1 shows the structural diagram of a radio sounding system with a packet method for transmitting telemetric information, which shows:

1 - meteorological parameters of the atmosphere (MPA), namely: temperature, pressure, humidity, etc .; 2 - aerological digital radiosonde (ARZ); 3 - block of primary and secondary converters MPA (BPVP); 4 - microcontroller ARZ (MK); 5 - interface device; 6 - calculator; 7 - shaper and modulator of the super-voltage super-regenerative transceiver (SPP); 8 - auto-bias circuit (AC); 9 - microwave-oscillator SPP; 10 - block preflight training (BPP) ARZ; 11 - control unit and recording parameters ARZ; 12 - pre-flight training console (IFR); 13 - the radar itself; 14 - radar transceiver (PPU); 15 - radar control system; 16 - block decoding PTI; 17 - block secondary processing of TI and issuing MPA; A1 - ARZ antenna; A2 - radar antenna; RK is a radio channel, M1 is a bi-directional communication bus, M2 is a unidirectional communication bus.

The system as a whole of FIG. 1 has the following connections. The meteorological parameters of the atmosphere of MPA 1 are connected to the weather inputs of ARZ 2, the output of which through the antenna A1 via a radio channel is connected to the antenna A2 of the radar 13; radar output 13 is connected to MPA consumers. The pre-flight preparation unit BPP 10 with a bi-directional bus is connected to the microcontroller MK 4 of the ARZ 2 radiosonde.

Figure 2 shows time charts explaining the principle of transmitting telemetric information in serial CP type AVK-MP3. Figure 2 shows the complete time cycle T _{c the} operation of the measuring generator of the radio probe MP3-3, including the time intervals of the reference channel T _op ; temperature channel T _t , humidity channel T _u , pressure channel T _d serial CP type AVK-MRZ.

Figure 3 shows a fragment of the proposed structure of a digital package of telemetric information ARZ in time scale.

Figure 4 shows the structure of the information package.

These nodes and CP blocks can be performed on the following elements: temperature and humidity sensors 3 can be performed, for example, according to the patents of the Russian Federation No. 2162238, No. 2162239, No. 2242752; pressure sensor 3 can be made on the basis of MPX type sensors (see MOTOROLA CATALOG, 2007); a measuring transducer can be implemented according to patent No. 54462; the interface device 5, the calculator and former of the PTI 6, the generator and modulator of the supervising voltage SPP 9 can be performed on the microcontroller MK 4, which can be implemented, for example, on microcircuits of the LPC2101FBD48 family (see ARM7 microcontrollers. Translated from English - M. : Dodeca-XX1, 2006); auto-bias circuit AS SPP 8, Microwave-AG SPP 7, antenna A1 can be made according to the materials of Russian patents No. 2172965, No. 2214614, No. 2470323, patents for utility models No. 50682, No. 49283, No. 56001; standard aerological radar 13 can be used of the type AVK-1, MARL, Vector-M, (see Ivanov V.E., Fridzon MB, Yesyak SP Radio sounding of the atmosphere. Technical and metrological aspects of development and application radiosonde measuring tools, edited by V.E. Ivanov, Yekaterinburg: Ural Branch of the Russian Academy of Sciences, 2004. 596 pp. ISBN 5-7691-1513-0); PTI 15 decoding unit and TI secondary processing unit and MPA 17 output can be implemented on microchips of the LPC2101FBD48 family (see ARM7 Microcontrollers. Transl. from English - M.: Dodeka-XX1, 2006).

The proposed radar CP with packet transmission of telemetry information works as follows.

At the CP input, the meteorological parameters of the atmosphere (MPA) 1: temperature, humidity, pressure. The ARZ 2 aerological radiosonde includes: a block of primary (sensors) and secondary (measuring) transducers MPA 3, a microcontroller ARZ MK 4, which respectively includes: a coupler 5, a transmitter and a shaper of packet telemetry information (PTI) 6, a shaper and SPP 9 supervising voltage modulator; SPP includes the autoset circuit AC SPP 8, the microwave autogenerator SHF-AG SPP 7 and the transceiver antenna A1. The ARZ 10 pre-flight preparation device includes an ARZ 11 monitoring and recording unit and ARZ 12 pre-flight preparation unit. The ground-based radar 13 includes: A2 transceiver antenna, radar 14 transceiver, PTI 15 decoding unit, radar control system 16 and unit secondary processing of telemetric information (TI) and the issuance of MPA 17 to the consumer of information MPA.

Preflight preparation unit 10 is designed to enter information about the primary parameters of the ARZ (operating frequency of the transmitter, calibration coefficients of the sensors) and monitor its operation before launch. Using the ARZ 12 preflight preparation console, the ARZ parameters monitoring and recording unit, information is loaded via the RS-232 type I / O interface into the MK 4 microcontroller of the ARZ 2 radiosonde. Meteorological atmospheric parameters MPA 1, for example, temperature, humidity, pressure, affect the primary unit (sensors) and secondary (measuring) transducers ARZ 3, the output electrical signals of which in the form of a voltage level, frequency or duration of video pulses are fed to the input of the interface device 5, the output of which is in the form The digital code is supplied to a calculator and a generator packet telemetry information (PTI) 6 microcontroller 4. The calculator 6 occurs statistical processing telemetry data obtained from each sensor during a measurement cycle of 2 seconds. In each measurement cycle, the determination of all MPA is provided for 2 seconds. Next, in the processor MK 4 is formed a digital packet of telemetric information, Fig.3. A number of overhead information is introduced into the packet structure, which ensures the synchronization of telemetric channels within the packet and synchronization of the current packet stream, which then goes to the input of the SPP ARZ, Fig. 4. The SPP contains a generator and a modulator of a super-voltage 9, an auto-bias circuit 8, a microwave oscillator, and a transceiver antenna A1.

The generator and modulator of the supervising voltage are implemented in the structure of MK 4, their parameters are regulated by software. The principle of operation of the SPP and methods for modulating its radiation are described in detail in RF patents No. 2172965, No. 2214614, No. 2470323, utility patents No. 50682, No. 49283, No. 56001.

The signal emitted by the ARZ 2 containing the telemetric information in a packet form is received by the A2 antenna with a narrow radiation pattern on the earth radar 13. The radar control system 15 provides synchronization of the operation of all devices and radar units 13. The technology for measuring the current coordinates of the ARZ, namely the inclined range using the pulsed method , angular coordinates using the equal-signal zone method, is described in primary sources (Efimov A.A. Principles of operation of the aerological information-computer complex AVK-1. - M.: Gidrometeoizdat, 1989. 149 p.; Zaitseva .A. Aerology. Gidrometeoizdat, 1990. 325 pp.). The ARZ radio signal is optimally processed in the telemetry channel of the radar receiver and in the form of a digital video pulse stream is fed to the input of the packet telemetry information decoding unit 14, in which the packet information is decoded and generated in the form of channel telemetric signals in digital form proportional to temperature, humidity, pressure. From the output of the decoding unit PTI 14, the information is fed to the input of the secondary processing unit for telemetric information (TI) 16, in which it is processed and presented in the form of meteorological parameters of the atmosphere (MPA): graphical dependences of temperature, humidity, pressure on the elevation of the ARZ, standard aerological telegrams for different MPA consumers.

To ensure the necessary accuracy of converting telemetric information, generating the exact time of the radiosonde operation cycles, stabilizing the super-power (subcarrier) frequency of the SPP and its modulation value, synchronizing signals in ARZ 2, the MK 4 microcontroller is used. When using the MK 4 processor, all functions for the operation of the radiosonde are programmed . MK 4 programming, input-output of technological information during the production and operation of ARZ is carried out via the RS-232 serial interface. The use of MK in an aerological radiosonde allows implementing modern more effective methods for modulating the parameters of the subcarrier frequency, for example, binary frequency (PFM) and phase (PIM) pulse modulation of the superficial frequency (BPSK). The implementation of the PFM and PIM superficial frequency using MK is carried out programmatically. In this case, the reception and demodulation of the telemetric signal of the ground-based radar is much simpler, because the reference signal necessary for the normal operation of the frequency or phase detector in the telemetry channel of the radar receiver is easily synchronized with a stable frequency of superimposing pulses. The most important task of MK 4 is the formation of a batch mode for transmitting telemetric information. Packets are transmitted in one-way (simplex) mode from a radiosonde to an aerological complex. Bit information is transmitted by the well-known method of pulse frequency modulation (PFM) subcarrier (superimposed) frequency SPP.

Since the information frequency band of coordinate-telemetric information does not exceed ΔF <0.5 Hz [1], its updating is carried out at a rate of at least once every two seconds. The redundancy introduced into the radio channel makes it possible to correct individual bit errors that may occur due to interference and to duplicate packets repeatedly to combat signal fading (mainly due to spatial oscillations of the ARZ). The data transfer rate in the channel is 2.4 kbps. The bit encoding method is a self-synchronizing code of the Manchester 2 type. The packet is transmitted unchanged for 2 seconds. Upon completion of the transfer of the current packet, the transmission of a new packet immediately begins. There are no temporary pauses between packets. The package consists of two parts. The first part is the rapidly changing information. The second part is additional information, which is transmitted much less frequently. The parameter number and its value are always transmitted. The structure of one of the options for the information packet transmitted by the ARZ is shown in FIG. 3, FIG. 4. The total packet length is 30 bytes · 8 = 240 bits. For a transmission speed of 2400 bps, this means that 20 identical packets are transmitted in 2 seconds. Thus, telemetric information in a packet is transmitted 200 times faster than in the known mode. Such redundancy eliminates the need for error-correcting coding. Error bit recovery is performed by correlation analysis of several adjacent packets. The telemetry channel data is transmitted in the packet body, this is the primary measurement data (temperature, humidity, pressure, etc.) and additional auxiliary data in the backup channel. It is important to note that the batch method of transmitting information from the radiosonde allows using any type of meteorological sensors as primary transducers that meet the requirements for accuracy of calibration of the static conversion characteristic (SHP), safety, and dynamic parameters.

To decrypt telemetry information packages, it is necessary to modernize the MARL, "Vector-M" radar by introducing a special subprogram, which is part of the radar system software, as a decoding unit for PTI 15. At the same time, standard interfacing with the secondary processing unit of the TI and the issuance of MPA 17 is ensured. All other characteristics of the radar and the CP radio channel are the width of the SPP emission spectrum, sensitivity to the range channel interrogation signal, radiated power of the ARZ, etc. fully comply with the requirements of technical specifications on SR.

In general, the use of packet transmission of telemetry information in radar CP allows you to:

- reduce the duration of the information transfer cycle to 1-2 seconds, thereby increasing the reliability of receiving telemetric information in conditions of strong fading ARZ signal;

- reduce the level of parasitic amplitude modulation (PAM) of the ARZ signal due to the more uniform character of the PTI and increase the stability of automatic tracking of the ARZ in angular coordinates;

- remove restrictions on the duration of the periods of the ARZ measuring transducer and expand the possibility of using various types of MPA sensors;

- significantly simplify the conditions for receiving and processing a signal in a radar receiver, thereby improving the reliability of receiving telemetric information.

Thus, when using the package method proposed in the application materials for transmitting telemetric information from the ARZ to the ground-based radar, the operational characteristics of domestic radar SRs significantly increase.

Claims (3)

1. Atmospheric radio sounding system with packet data transmission, comprising an aerological radiosonde - ARZ and a base station - radar, characterized in that the ARZ pre-flight preparation unit consisting of a pre-flight preparation console and an ARZ parameters monitoring and recording unit with the following connections is included in the ARZ: the ARZ pre-flight preparation console is connected to the inputs of the ARZ microcontroller via the ARZ parameters monitoring and recording unit; a radar unit for decoding packet teleinformation and a unit for secondary processing of teleinformation and issuing signals of atmospheric meteorological parameters with the following connections were introduced: a unidirectional bus M2 of a transceiver radar unit is connected via a decoding unit for packet teleinformation with a unit for secondary processing of teleinformation and issuing atmospheric meteorological parameters, the output of which is the output system. 2. The system according to claim 1, characterized in that the pre-flight preparation unit is made by a separate construct and is connected to an aerological radio probe for the time of entering the packet information format, also, at the request of the customer, can be solved programmatically in the ARZ microcontroller. 3. The system according to claim 1, characterized in that the upper-air radiosonde transceiver is designed according to a super-generator circuit and includes serially connected: a generator and a super-voltage modulator, an auto bias circuit and a microwave oscillator loaded on the antenna.

Images