CN103634254A - Indirect modulation and demodulation data transmission device and transmission method thereof - Google Patents
Indirect modulation and demodulation data transmission device and transmission method thereof Download PDFInfo
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Abstract
The invention discloses an indirect modulation and demodulation data transmission device. The device comprises: an error correction coding module; a modulation module which is connected with the error correction coding module; an emission filter module which is connected with the modulation module; a waveform amplitude adjustment and emission switch control module which is connected with the emission filter module; a gain control module; a reception filter module which is connected with the gain control module; a demodulation module which is connected with the reception filter module; and an error correction decoding module which is connected with the demodulation module. The invention also discloses a transmission method of the indirect modulation and demodulation data transmission device. The indirect modulation and demodulation data transmission device modulates digital information into base-band modulation signals within an audio frequency band and realizes a function of digital information transmission of an ultrashort wave telephone traffic radio station; besides, the indirect modulation and demodulation data transmission device is low in implementation cost and strong in universality, does not change the original structure of a radio station, and is convenient to large-scale popularization.
Description
Technical field
The present invention relates to utilize ultra short wave communication equipment to carry out the technique device of transfer of data, relate in particular to a kind of indirect modulation /demodulation number and pass device and transmission method thereof.
Background technology
The application of current plain edition ultrashort wave radio set function be take traffic call, phonic communication as main, such as the ship platform deck of operation on the sea naval vessel standard configuration, various uses aircraft equipment airborne, the widely used all kinds of Vehicle mounted stations in ground and base station etc.Although the traffic radio station of simple function exist use and understand on convenience, transmission of speech information is easily explained or is listened and debate mistake, and cannot transmit more complicated digital information, inefficiency.Follow all kinds of terminal equipment digitlizations, automaticity to improve, the proportion of data service in ultra short wave communication is just in fast rise.There is in the market the ultrashort wave radio set purchase cost of number/words dual mode capability significantly higher than common traffic radio station, cause adopting novel number/words dual mode radio to build the high expensive of ultrashort wave number telephone network; While adopting new radio station mode to implement networking or systemic-function upgrading, also there will be the unfavorable situation that the huge active service traffic radio station of quantity is idle, waste simultaneously.
Summary of the invention
The present invention has overcome the above-mentioned defect of prior art, has proposed a kind of indirect modulation /demodulation number and has passed device and transmission method thereof.The present invention adopts indirect modulation technique, by digital information modulation conversion, be the baseband modulation signal of similar traffic audio volume control the voice transfer passage that imports traffic radio station, after follow-up intermediate frequency Modulation, rf conversion processing are carried out in ultrashort wave traffic radio station, broadcast.This digital information transmission mode does not change original traffic broadcasting station structure and interface shape, by external indirect modulation /demodulation number of the present invention, pass device and realized the transfer of data in ultrashort wave traffic radio station, expanded the single traffic function in former ultrashort wave traffic radio station, in technology enforcement and engineering application aspect, all had well and produce effects.
The present invention proposes a kind of indirect modulation /demodulation number and pass device, comprising:
Error correction coding module, its data message for input carries out the processing of channel error correction coding;
Modulation module, it is connected with described error correction coding module, and described data message after error correction coding is processed is carried out to sign map processing, forms audio base-band modulation signal;
Emission filter module, it is connected with described modulation module, and described audio base-band modulation signal is carried out to shaping filter processing;
Wave-shape amplitude is adjusted and emission switch control module, and it is connected with described emission filter module, and described audio base-band modulation signal after shaping filter is processed is carried out amplitude adjustment and controls output;
Gain control module, it carries out signal amplitude adjustment processing for the audio base-band modulation signal receiving;
Receiving filter module, it is connected with described gain control module, and the audio base-band modulation signal after described amplitude adjustment is carried out to filter shape processing;
Demodulation module, it is connected with described receiving filter module, and the audio base-band modulation signal of described Shape correction is after filtering carried out to demodulation process, obtains digital signal;
Error-correcting decoding module, it is connected with described demodulation module, and described digital signal is carried out to error-correcting decoding processing, obtains data message.
Wherein, described error correction coding module is RS code error correction coding module.
Wherein, described error-correcting decoding module is RS code error-correcting decoding module.
Wherein, described modulation module is 8-Level CPFSK modulation module, GMSK modulation module.
Wherein, described demodulation module is 8-Level CPFSK demodulation module, GMSK demodulation module.
The present invention proposes the transmission method that a kind of indirect modulation /demodulation number passes device, comprise secondary modulation mode and secondary demodulation mode.
Wherein, described secondary modulation mode comprises:
Steps A 1: described error correction coding module receives from the data message of described data module output, and described error correction coding module is carried out error correction coding processing to described data message, is sent to described modulation module;
Steps A 2: the data message of described modulation module after to described error correction coding carries out sign map processing, obtains audio base-band modulation signal and is sent to emission filter module;
Steps A 3: described emission filter module is carried out shaping filter processing to described audio base-band modulation signal, is sent to described wave-shape amplitude adjustment and emission switch control module;
Steps A 4: described wave-shape amplitude adjustment and emission switch control module are carried out amplitude adjustment to described audio base-band modulation signal and exported described ultrashort wave traffic radio station to.
Wherein, described secondary demodulation mode comprises:
Step B1: described gain control module receives the audio base-band modulation signal in described ultrashort wave traffic radio station, and described audio base-band modulation signal is carried out to signal amplitude adjustment processing, be sent to the described filter module of accepting;
Step B2: the audio base-band modulation signal of described receiving filter module after to described amplitude adjustment carries out filter shape processing, is sent to described demodulation module;
Step B3: described demodulation module carries out demodulation process to described audio base-band modulation signal, obtains digital signal and is sent to described error-correcting decoding module;
Step B4: described error-correcting decoding module is carried out error-correcting decoding processing to described digital signal, obtains data message and is sent to data module.
The invention allows for a kind of ultrashort wave wireless data sending application system, comprising: ultrashort wave traffic radio station, indirect modulation /demodulation number pass device and data module;
Described ultrashort wave traffic radio station, it is connected with described indirect modulation /demodulation number biography device, for modulating and send radiofrequency signal and receiving ultrashort wave signal;
Described data module, it is connected with described indirect modulation /demodulation number biography device, as described user service data terminal, realizes data processing.
Wherein, described ultrashort wave traffic radio station comprises:
Audio-frequency module, it passes device with described indirect modulation /demodulation number and is connected, described audio base-band modulation signal audio signal filtering and amplitude are amplified to processing, and realize routing switching, the PTT control signal logical process of outside line audio frequency and radio station microphone audio frequency and generate radio station complete machine transmitting keying signal;
Ifd module, it is connected with described audio-frequency module, described audio base-band modulation signal is carried out to intermediate frequency Modulation and generate modulated intermediate frequency signal, and the ultrashort wave signal receiving is carried out to demodulation, obtains audio base-band modulation signal;
Radio-frequency module, it is connected with described ifd module, for mixing and the described modulated intermediate frequency signal of excitation, obtains radiofrequency signal;
Transmit-receive switch and antenna, it is connected with radio-frequency module, for regulating the reiving/transmitting state in described ultrashort wave traffic radio station, realizes and sends described radiofrequency signal or receive described ultrashort wave signal.
The transmission method that the invention allows for a kind of ultrashort wave wireless data sending application system, comprises transmitted signal mode and signal reception mode.
Wherein, described transmitted signal mode comprises:
Step C1: described error correction coding module receives from the data message of described data module output, and described error correction coding module is carried out error correction coding processing to described data message, is sent to described modulation module;
Step C2: the data message of described modulation module after to described error correction coding carries out sign map processing, obtains audio base-band modulation signal and is sent to emission filter module;
Step C3: described emission filter module is carried out shaping filter processing to described audio base-band modulation signal, is sent to described wave-shape amplitude adjustment and emission switch control module;
Step C4: described wave-shape amplitude adjustment and emission switch control module are carried out amplitude adjustment and exported described audio-frequency module to described audio base-band modulation signal;
Step C5: described audio-frequency module carries out routing switching, filtering and amplifies and process described audio base-band modulation signal, is sent to described ifd module; The transmitting keying signal that described audio-frequency module generates described radio station complete machine is simultaneously to described transmit-receive switch and antenna;
Step C6: described ifd module carries out intermediate frequency Modulation to described audio base-band modulation signal, obtains modulated intermediate frequency signal and is sent to described radio-frequency module;
Step C7: described radio-frequency module carries out mixing to described modulated intermediate frequency signal and amplifies and process with excitation, obtains radiofrequency signal;
Step C8: described transmit-receive switch and antenna are adjusted to emission state according to the transmitting keying signal of described radio station complete machine by described ultrashort wave traffic radio station, and described transmit-receive switch and antenna are sent to spacing wireless channel by described radiofrequency signal.
Wherein, described signal reception mode comprises:
Step D1: described transmit-receive switch and antenna are adjusted to accepting state by described ultrashort wave traffic radio station, described transmit-receive switch and antenna reception are to the ultrashort wave signal from spacing wireless channel;
Step D2: described ifd module carries out intermediate frequency demodulation processing to described ultrashort wave signal, obtains audio base-band modulation signal and is sent to described audio-frequency module;
Step D3: described audio-frequency module carries out audio frequency output to described audio base-band modulation signal, and described audio base-band modulation signal is sent to described gain control module;
Step D4: described gain control module receives the audio base-band modulation signal of described audio-frequency module, and described audio base-band modulation signal is carried out to signal amplitude adjustment processing, be sent to the described filter module of accepting;
Step D5: the audio base-band modulation signal of described receiving filter module after to described amplitude adjustment carries out filter shape processing, is sent to described demodulation module;
Step D6: described demodulation module carries out demodulation process to described audio base-band modulation signal, obtains digital signal and is sent to described error-correcting decoding module;
Step D7: described error-correcting decoding module is carried out error-correcting decoding processing to described digital signal, obtains data message and is sent to data module;
Step D8: described data module is carried out subsequent treatment to described data message.
The indirect modulation /demodulation number of the present invention passes device can, in the situation that structure and the information transmission mode thereof in original ultrashort wave traffic radio station do not change, realize digital information transmission by indirect modulation.
The present invention adopts indirect modulation technique, can be with the information of the mode transmission of digital signals of audio base-band modulation signal.If do not use the radio station of the indirect modulation technique of the present invention cannot demodulate the digital signal in audio base-band modulation signal, there is higher fail safe.
The data processing method that the present invention can upgrade in modulation /demodulation module, error correction coding decoding module changes, and maintenance cost is low.
Indirect modulation /demodulation number of the present invention passes device and adopts RS232/RS485 serial line interface to be connected with miscellaneous part, has good function expansibility with compatible.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of ultrashort wave wireless data sending application system of the present invention;
Fig. 2 is the connection diagram that the indirect modulation /demodulation number of the present invention passes device;
Fig. 3 is the hardware circuit schematic diagram of ultrashort wave wireless data sending application system in the present invention;
Fig. 4 is the schematic diagram that uses ultrashort wave wireless data sending application system of the present invention;
Fig. 5 is the product process schematic diagram of RS error correction coding in the present invention.
Embodiment
In conjunction with following specific embodiments and the drawings, the present invention is described in further detail.Implement process of the present invention, condition, experimental technique etc., except the content of mentioning specially below, be universal knowledege and the common practise of this area, the present invention is not particularly limited content.
As Figure 1-5,1-ultrashort wave traffic radio station, the indirect modulation /demodulation number of 2-passes device, 3-data module, 11-audio-frequency module, 12-ifd module, 13-radio-frequency module, 14-transmit-receive switch and antenna, 21-error correction becomes code module, 22-modulation module, 23-emission filter module, 24-wave-shape amplitude is adjusted and emission switch control module, 25-gain control module, 26-receiving filter module, 27-demodulation module, 28-error-correcting decoding module.
Indirect modulation /demodulation number of the present invention passes device 2, as shown in Figure 2, comprising:
Error correction coding module 21, its data message for input carries out the processing of channel error correction coding;
Wave-shape amplitude is adjusted and emission switch control module 24, and it is connected with emission filter module 23, and the audio base-band modulation signal after shaping filter is processed is carried out amplitude adjustment and controls output;
Receiving filter module 26, it is connected with gain control module 25, and the audio base-band modulation signal after amplitude adjustment is carried out to filter shape processing;
Error-correcting decoding module 28, it is connected with demodulation module 27, and digital signal is carried out to error-correcting decoding processing, obtains data message.
Error correction coding module 21 of the present invention is RS code error correction coding module.Error-correcting decoding module 28 is RS code error-correcting decoding module.Modulation module 22 is 8-Level CPFSK modulation module, GMSK modulation module.Demodulation module 27 is 8-Level CPFSK demodulation module, GMSK demodulation module.
Indirect modulation /demodulation number of the present invention passes the radio station that device 2 is structurally independent of standard model, and belonging to third party provides equipment, traffic radio station can be expanded in function to number/words dual mode radio while being used in conjunction with common traffic radio station.The 1 Function Extension application in ultrashort wave traffic radio station, or the built fields such as ultrashort wave traffic network function upgrading have explicit costs comparison advantage.
Indirect modulation /demodulation number of the present invention passes device 2, and it is arranged between data terminal 3 and ultrashort wave traffic radio station 1.Modulation /demodulation number biography device 2 is connected with the data terminal of customer service application by standardized RS232/RS485 serial line interface standard indirectly.By ultrashort wave traffic radio station 1 outside line audio interface, be connected to the audio-frequency module 11 in ultrashort wave traffic radio station 1, this interface adopts multi-thread cable connected mode, wherein comprised audio signal and received line, audio signal transmission line, GND signal ground line, PTT transmission control line, VCC direct current supply line, GND power ground line, for carrying out the I/O of audio base-band modulation signal and providing the operation of this device required direct current power supply.
The main hardware circuit platform that indirect modulation /demodulation number of the present invention passes device 2 comprises, as shown in Figure 3:
High performance 16 fixed DSP digital signal processing chips, arithmetic speed is more than 80MIPS.
8 AVR MCU microcontrollers, send control, intermodule various types of communication agreement for realizing PTT.Based on the high efficiency C CompilerTools of AVR, this device has good structural and maintainable.AVR MCU is supported in sequence of threads and upgrades, and this feature is supported the field upgrade of this device hardware system program.
The ware circuit of apparatus of the present invention has adopted universal modem hardware platform, and all modulation /demodulation all realizes in the mode of module.Based on this hardware system platform, can on same hardware platform, realize 8-Level CPFSK, GMSK or other number of types tone of Chinese characters modulation demodulation system, be convenient to system upgrade or the Function Extension realized.
First the present invention is modulated into audio baseband signal by digital information, the voice channel that this audio base-band modulation signal is imported to ultrashort wave traffic radio station 1 is again broadcast, and ultrashort wave traffic radio station 1 is expanded to and have the ultrashort wave wireless data sending application system of the present invention of counting/talking about dual mode communication ability.Ultrashort wave wireless data sending application system has inclusion relation for former traffic radio station, do not change former broadcasting station structure, function and signal processing, just increased on its basis independently indirect modulation /demodulation number newly and passed device 2, and the signal adaptation having realized between the two by former radio station outside line audio interface connects.The invention provides a kind of Implementation Technology that uses ultrashort wave traffic radio station 1 to realize data/speech dual-transfer mode; the simple function ultrashort wave traffic radio station 1 huge for current quantity on hand provides a kind of effective way of carrying out function upgrading, application extension; avoid the unfavorable situation that this type of radio station is idle, waste, effectively protected existing equipment investment.Relatively adopt number/words bimodulus ultrashort wave traffic radio station 1 of newly purchasing of reactance modulation system to carry out application system structure, apparatus of the present invention have obvious comparison advantage at aspects such as construction cost, engineering construction, operation maintenance, Function Extension/upgrading flexibilities.
Ultrashort wave wireless data sending application system of the present invention, as shown in Figure 1, comprising: ultrashort wave traffic radio station 1, indirect modulation /demodulation number pass device 2 and data module 3.
Ultrashort wave traffic radio station 1, it is connected with indirect modulation /demodulation number biography device 2, for modulating and send radiofrequency signal and receiving ultrashort wave signal; Ultrashort wave traffic radio station 1 is standard type radio station conventional in prior art, for example common radio station.
Ultrashort wave traffic of the present invention radio station 1 comprises:
Audio-frequency module 11, it passes device 2 with indirect modulation /demodulation number and is connected, audio base-band modulation signal is carried out to audio signal filtering and amplitude amplification processing, and realize routing switching, the PTT control signal logical process of outside line audio frequency and radio station microphone audio frequency and generate radio station complete machine transmitting keying signal;
Radio-frequency module 13, it is connected with ifd module 12, for mixing and excitation modulated intermediate frequency signal, obtains radiofrequency signal;
Transmit-receive switch and antenna 14, it is connected with radio-frequency module 13, for regulating the reiving/transmitting state in ultrashort wave traffic radio station 1, realizes and sends radiofrequency signal or receive ultrashort wave signal.
Indirect modulation system of the present invention is relatively directly modulation.Generally, the analog or digital communication service in ultrashort wave traffic radio station 1 generally adopts intermediate frequency Modulation (i.e. directly modulation), using middle frequency sine-wave as carrier wave, the direct centering frequency sine-wave of modulation signal is modulated, modulated intermediate-freuqncy signal is transformed into emission of radio frequency signals after mixing, only relates to primary modulation process in this process.The audio signal modulation in common ultrashort wave traffic radio station 1 adopts analog intermediate frequency modulation classification, as modulating FM, amplitude modulation AM, single-side belt SSB etc.; The data message modulation in the dual-purpose radio station of the ultrashort wave number of novel standard/talk about adopts digital system intermediate frequency Modulation, and as FSK, PSK etc., above-mentioned common traffic radio station and number/talk about dual-purpose radio station all belong to direct modulation type.
When the present invention adopts indirect modulation system, first using the sine wave of lower base band frequency as carrier wave, 22 pairs of base band sine waves of modulation module are modulated, and generate base band tonal signal; By base band modulated signal as modulation signal, sine wave by 12 pairs of IF-FRE of ifd module carries out intermediate frequency Modulation again, obtain modulated intermediate frequency signal, modulated intermediate frequency signal forms emission of radio frequency signals after mixing conversion, in this process, related to twice modulated process, therefore modulation claims again secondary modulation indirectly.
Indirect modulation /demodulation number of the present invention passes device 2, according to function is different with signal processing flow, can be divided into secondary modulation and secondary demodulation.The present invention adopts identical DSP Digital Signal Processing and MCU microcontroller integrated circuit (IC) platform when realizing secondary modulation with secondary demodulation, by different modules, has realized corresponding signal processing capacity.
Indirect modulation /demodulation number of the present invention passes the transmission method of device 2, comprises secondary modulation mode and secondary demodulation mode.
Wherein, secondary modulation mode of the present invention comprises:
Steps A 1: error correction coding module 21 receives from the data message of data module 3 outputs, and 21 pairs of data messages of error correction coding module carry out error correction coding processing, are sent to modulation module 22;
Steps A 2: the data message after 22 pairs of error correction codings of modulation module carries out sign map processing, obtains audio base-band modulation signal and is sent to emission filter module 23;
Steps A 3: 23 pairs of audio base-band modulation signals of emission filter module carry out shaping filter processing, are sent to wave-shape amplitude adjustment and emission switch control module 24;
Steps A 4: 24 pairs of audio base-band modulation signals of wave-shape amplitude adjustment and emission switch control module carry out amplitude adjustment and export ultrashort wave traffic radio station 1 to.
Wherein, secondary demodulation mode of the present invention comprises:
Step B1: gain control module 25 receives the audio base-band modulation signal in ultrashort wave traffic radio station 1, and audio base-band modulation signal is carried out to signal amplitude adjustment processing, is sent to receiving filter module 26;
Step B2: the audio base-band modulation signal after 26 pairs of amplitude adjustment of receiving filter module carries out filter shape processing, is sent to demodulation module 27;
Step B3: 27 pairs of audio base-band modulation signals of demodulation module carry out demodulation process, obtain digital signal and are sent to error-correcting decoding module 28;
Step B4: 28 pairs of digital signals of error-correcting decoding module are carried out error-correcting decoding processing, obtain data message and are sent to data module 3.
The transmission method of ultrashort wave wireless data sending application system of the present invention, comprises transmitted signal mode and signal reception mode.
Wherein, ultrashort wave wireless data sending application system transmitted signal mode of the present invention comprises:
Step C1: error correction coding module 21 receives from the data message of data module 3 outputs, and 21 pairs of data messages of error correction coding module carry out error correction coding processing, are sent to modulation module 22;
Step C2: the data message after 22 pairs of error correction codings of modulation module carries out sign map processing, obtains audio base-band modulation signal and is sent to emission filter module 23;
Step C3: 23 pairs of audio base-band modulation signals of emission filter module carry out shaping filter processing, are sent to wave-shape amplitude adjustment and emission switch control module 24;
Step C4: 24 pairs of audio base-band modulation signals of wave-shape amplitude adjustment and emission switch control module carry out amplitude adjustment and export audio-frequency module 11 to;
Step C5: 11 pairs of audio base-band modulation signals of audio-frequency module carry out routing switching, filtering and amplify and process, and are sent to ifd module 12; The transmitting keying signal that audio-frequency module 11 generates radio station complete machine is simultaneously to transmit-receive switch and antenna 14;
Step C6: 12 pairs of audio base-band modulation signals of ifd module carry out intermediate frequency Modulation, obtain modulated intermediate frequency signal and are sent to radio-frequency module 13;
Step C7: 13 pairs of modulated intermediate frequency signals of radio-frequency module carry out mixing and amplify and process with excitation, obtain radiofrequency signal;
Step C8: transmit-receive switch and antenna 14 are adjusted to emission state by ultrashort wave traffic radio station 1 by ultrashort wave traffic radio station 1 according to the transmitting keying signal of radio station complete machine, transmit-receive switch and antenna 14 are sent to spacing wireless channel by radiofrequency signal.
The signal transmission flow of ultrashort wave wireless data sending application system of the present invention is:
Next step is sent to modulation module 22 digital information flow after RS error correction coding is processed, completes digital information to the sign map process of audio base-band modulation signal.Continuous phase frequency shift keying CPFSK can avoid the discontinuous high fdrequency component causing because of phase place, and Bandwidth-Constrained channel is had to good adaptive capacity, at digital communicating field, is widely adopted.8-Level CPFSK Digital Modulation is a kind of high-order modulating, and the data content that each symbol waveform has comprised 3bit can support this device to realize the ultrashort wave message transmission rate up to 19.2kbps.
Baseband modulation waveform after modulation module 22 sign map are processed contains a large amount of higher harmonic components, and ultrashort wave traffic radio station 1 allows the bandwidth of input audio signal generally below 10k, first emission filter module 23 carries out molding filtration to baseband modulation waveform, its baseband waveform bandwidth is controlled to the allowed band in ultrashort wave traffic radio station 1.The emission filter module 23 that the present invention adopts is raised cosine low pass filter, and its definition is shown in shown in following formula (I):
Wherein, b=0.2, the time width that T is code element, i.e. T=1/symbol rate.
The general half-duplex mode that adopts in ultrashort wave traffic radio station 1, signal transmitting and receiving is positioned at same frequency range, during signal demand transmitting, by PTT button, starts emission switch, and talk-through discharges PPT button and recovers channel-monitoring accepting state in ultrashort wave traffic radio station 1.Indirect modulation /demodulation number of the present invention passes device 2 and is controlled by MCU, according to whether having outgoing data automatically to control transmit-receive switch and antenna 14, and implement the amplitude adjustment of audio base-band modulation signal, afterwards signal is sent to the audio-frequency module 11 in ultrashort wave traffic radio station 1, completes this device Multi-modulation signal handling process.The audio base-band modulation signal that is directed into radio station traffic channel will be by broadcasting to spacing wireless channel after the conversion process such as ultrashort wave traffic radio station 1 internal implementation intermediate frequency Modulation, RF excited.
The signal reception mode of ultrashort wave wireless data sending application system of the present invention comprises:
Step D1: transmit-receive switch and antenna 14 are adjusted to accepting state by ultrashort wave traffic radio station 1, transmit-receive switch and antenna 14 receive the ultrashort wave signal from spacing wireless channel;
Step D2: 12 pairs of ultrashort wave signals of ifd module carry out intermediate frequency demodulation processing, obtains audio base-band modulation signal and is sent to audio-frequency module 11;
Step D3: 11 pairs of audio base-band modulation signals of audio-frequency module carry out routing switching, filtering and amplify and process, and audio base-band modulation signal is sent to gain control module 25;
Step D4: the audio base-band modulation signal of gain control module 25 audio reception modules 11, and audio base-band modulation signal is carried out to signal amplitude adjustment processing, be sent to and accept filter module 26;
Step D5: the audio base-band modulation signal after 26 pairs of amplitude adjustment of receiving filter module carries out filter shape processing, is sent to demodulation module 27;
Step D6: 27 pairs of audio base-band modulation signals of demodulation module carry out demodulation process, obtain digital signal and are sent to error-correcting decoding module 28;
Step D7: 28 pairs of digital signals of error-correcting decoding module are carried out error-correcting decoding processing, obtain data message and are sent to data module 3;
Step D8: 3 pairs of data messages of data module carry out subsequent treatment.
The signal of ultrashort wave wireless data sending application system of the present invention receives flow process:
Do not have in traffic call situation, ultrashort wave traffic radio station 1 is generally in channel-monitoring accepting state.The ultrashort wave signal that 12 pairs of ifd modules receive carries out intermediate frequency demodulation, obtains audio base-band modulation signal.For any audio base-band modulation signal on certain specific frequency, due to the opening of wireless channel, electric wave reception can be carried out in all monitorings radio station.For the indirect modulation wireless data sending application the present invention relates to, ultrashort wave traffic radio station 1 terminal only with demodulation module 27 of the present invention could realize correct demodulation, decoding receives; For other ultrashort wave traffic radio station 1, received signal shows as audio-frequency noise information.
Apparatus of the present invention receive the audio base-band modulation signal from audio-frequency module 11 outputs in ultrashort wave traffic radio station 1, first carry out the AGC automatic gain of gain control module 25 and control processing, and the audio base-band modulation signal of reception is adjusted to appropriate level; By receiving filter module 26, carry out clutter filtering again, be sent to afterwards demodulation module 27 and carry out demodulation process, data are reverted to binary digital information; Finally by error-correcting decoding module 28, carry out correction process, output data message is sent to data module 3 through RS232/RS485 interface, completes the secondary demodulation signal reception & disposal process of this device.
Embodiment 1:
The present embodiment is the application process of ultrashort wave wireless data sending application system.The indirect modulation /demodulation number of the present invention passes device 2 as a kind of digital information processing and signal-conversion equipment, coordinates with ultrashort wave traffic radio station 1, data module 3, jointly forms ultrashort wave wireless data sending application system.
In the present embodiment, the audio-frequency module 11 with the plain edition ultrashort wave traffic radio station 1 of single traffic function has configured microphone handle and boombox, for realizing traffic call and monitoring; Also dispose the outside audio interface that connects, in order to realize outer audio equipment expansion simultaneously.This outside audio interface that connects adopts multi-thread cable to connect, wherein comprise audio signal and received line, audio signal transmission line, GND signal ground line, PTT transmission control line, DC power line, GND power ground line, be respectively used to carry out modulating baseband signal I/O, PTT transmitting-receiving control and the supply of external function module power supply.The indirect modulation /demodulation number of the present invention passes device 2 and realizes the physical connection with ultrashort wave traffic radio station 1 by this outside audio interface that connects, and completes the concrete functions such as transmitting-receiving control in the output of audio base-band modulation signal and output, ultrashort wave traffic radio station 1.The remote application client that data module 3 is subscriber service system exists as information source or the stay of two nights in whole communication system forms.The indirect modulation /demodulation number of the present invention passes device 2 and adopts RS232/RS485 serial line interface standard to be connected with data module 3, RS232/RS485 interface is one of most widely used Standardization Communication interface of current Various types of data terminal equipment, adopts this interface to be conducive to promote compatibility of the present invention and ease for use.
Ultrashort wave wireless data sending application system of the present invention, according to functions of modules transmitted signal mode and the signal reception modes based on secondary demodulation that can be divided into based on secondary modulation different from signal processing flow.
The signal processing flow of the transmitted signal mode of ultrashort wave wireless data sending application system of the present invention is:
Step 1: data module 3 is delivered to by RS232/RS485 serial line interface the error correction coding module 21 that indirect modulation /demodulation number passes device 2 by data message stream to be sent, carries out the processing of channel error correction coding;
Step 2: the data message stream after error correction coding module 21 is processed is sent to modulation module 22 by internal bus, completes digital signal to the sign map of audio baseband signal and processes;
Step 3: 23 pairs of baseband modulation signals of emission filter module carry out molding filtration processing, its low-frequency filter characteristics filtering the higher harmonic components in baseband modulation waveform, its baseband waveform bandwidth is controlled to the allowed band in ultrashort wave traffic radio station 1;
Step 4: wave-shape amplitude adjustment and emission switch control module 24 are carried out the wave amplitude output intensity adjustment of baseband modulation signal according to ultrashort wave traffic radio station 1 for input audio signal gain facilities, and in detecting wireless channel idle situation, start PTT emission switch and carry out the audio-frequency module 11 that signal exports ultrashort wave traffic radio station 1 to;
Step 5: standardization is carried out in ultrashort wave traffic radio station 1 using the baseband modulation signal of input as traffic call is sent to spacing wireless channel by transmit-receive switch and antenna 14 after processing is amplified in intermediate frequency Modulation, radio-frequency module 13 frequency conversions and the excitation of ifd module 12.
The signal processing flow of the signal reception mode of ultrashort wave wireless data sending application system of the present invention is:
Step 1: under business call case, ultrashort wave traffic radio station 1 is in channel-monitoring, accepting state.When ultrashort wave traffic radio station 1 receives normal traffic call, according to existing standardization program, carry out traffic reception & disposal; When receiving signal and be data-signal, the indirect modulation /demodulation number of the present invention passes 2 pairs of audio base-band modulation signals from ultrashort wave traffic radio station 1 external audio connection line of device and starts demodulating processes;
Step 2: 26 pairs of baseband modulation signals that receive of gain control module 25 and receiving filter module carry out wave-shape amplitude adjustment and filter shape is processed;
Step 3: 27 pairs of gain control module 25 of demodulation module and the pretreated baseband modulation signal of receiving filter module 26 carry out demodulation process, recovers binary digital information stream;
Step 4: owing to having comprised possible signal errors, 28 pairs of above-mentioned binary digital information streams of error-correcting decoding module are processed, adjudicates, further recovers according to the redundant bit information decoding wherein comprising the primary data information (pdi) that former data terminal module is exported;
Step 5: the indirect modulation /demodulation number biography of the present invention device 2 is crossed RS232/RS485 serial line interface by the data receiver information exchange after processing and transferred to data module 3, thereby completes whole data information transfer process.
Embodiment 2:
Certain fishery has many marine fishing operation fishing boats, and because shoal of fish mobility is strong, neighbour's national marine line of demarcation exists dispute or it is clear not yet to define, fishing boat and operating personnel are often harassed or arrest button fine by other country, cause casualties and property loss.Fishery intends strengthening the remote monitoring and administration to fishing boat operation on the sea, obtains the data messages such as fishing boat real time position, meteorological condition and equipment running status, and assigns accordingly supervisory instruction.On fishing boat at present standard configuration for the plain edition ultrashort wave traffic radio station 1 of daily contact and distress call purposes; adopt the present invention to carry out function upgrading to former ultrashort wave traffic radio station 1; built up the ultrashort wave wireless data sending application system that meets the requirement of above-mentioned fishing boat remote supervisory, and engineering construction has that the cycle is fast, cost is low, do not change the model in original ultrashort wave traffic radio station 1 and out of my cabin antenna equipment, the remarkable advantages such as existing investment adequately protect.
Fig. 4 is that apparatus of the present invention are at the system framework schematic diagram of the embodiment in seagoing fishing vessel remote supervisory field.As shown in Figure 4, in ultrashort wave traffic radio station 1 data transmission system of the present embodiment, there is a management main station system A, comprising plain edition ultrashort wave traffic radio station 1 and sub-base platform antenna, the indirect modulation /demodulation number of the present invention, pass device 2, system monitoring supervisory computer etc.As shown in Figure 4, the ultrashort wave wireless data sending application system of the present embodiment also comprises some far-end substation systems that are positioned on ocean operation fishing boat, as far-end substation B, far-end substation C, far-end substation D, wherein each far-end substation system has comprised plain edition ultrashort wave traffic radio station 1, the indirect modulation /demodulation number of the present invention passes device 2, data module 3.
In the present embodiment, management main station system A receives the operation fishing boat operation information from far-end substation, and feeds back as the case may be fishing boat job instruction; Far-end substation B, C, D send fishing boat operation information to the A of system management main website, and accept the supervisory instruction of main station system A.
When fishing boat is carried out operation on the sea task, the data module 3 of far-end substation B, C, D receives the data message that all types of boat-carrying electronic equipments provide, as Current GPS coordinate, course, wind speed, shoal of fish resource detection information, powerplant module operation information etc., by this information according to certain prescribed manner gather, format conversion processing, and periodically this information is delivered to indirect modulation /demodulation number biography device 2, through ultrashort wave traffic radio station 1, broadcast to spacing wireless channel.Management main station system A receives from the above-mentioned information of operation on the sea fishing boat and monitors, assesses, while is the risk information about marine site, place with reference to relevant governability structures such as fish-farming operation, maritime affairs, meteorologies, find to exist while being not suitable for some factor of fishing operation, in time with traffic urgent call or data command form warning operation fishing boat or the disposal instruction of being correlated with.
By apparatus of the present invention, apply, above-mentioned fishery in 1 system-based of original ultrashort wave traffic radio station Rapid Implementation the remote automation supervision number of operation on the sea fishing boat pass function upgrading, for ensureing that operation on the sea personnel's life and property safety brought into play practical function effect.Meanwhile, relatively adopt the novel number/words dual mode radio networking mode of purchase, apparatus of the present invention application has the obvious comparison advantages such as cost is low, easy to operate, the existing investment of protection.
Protection content of the present invention is not limited to above embodiment.Do not deviating under the spirit and scope of inventive concept, the variation that those skilled in the art can expect and advantage portion are included in the present invention, and take appending claims as protection range.
Claims (13)
1. indirect modulation /demodulation number passes a device, it is characterized in that, comprising:
Error correction coding module (21), its data message for input carries out the processing of channel error correction coding;
Modulation module (22), it is connected with described error correction coding module (21), and described data message after error correction coding is processed is carried out to sign map processing, forms audio base-band modulation signal;
Emission filter module (23), it is connected with described modulation module (22), and described audio base-band modulation signal is carried out to shaping filter processing;
Wave-shape amplitude is adjusted and emission switch control module (24), and it is connected with described emission filter module (23), and described audio base-band modulation signal after shaping filter is processed is carried out amplitude adjustment and controls output;
Gain control module (25), it carries out signal amplitude adjustment processing for the audio base-band modulation signal receiving;
Receiving filter module (26), it is connected with described gain control module (25), and the audio base-band modulation signal after described amplitude adjustment is carried out to filter shape processing;
Demodulation module (27), it is connected with described receiving filter module (26), and the audio base-band modulation signal of described Shape correction is after filtering carried out to demodulation process, obtains digital signal;
Error-correcting decoding module (28), it is connected with described demodulation module (27), and described digital signal is carried out to error-correcting decoding processing, obtains data message.
2. modulation /demodulation number passes device indirectly as claimed in claim 1, it is characterized in that, described error correction coding module (21) is RS error correction coding module.
3. modulation /demodulation number passes device indirectly as claimed in claim 1, it is characterized in that, described error-correcting decoding module (28) is RS error-correcting decoding module.
4. modulation /demodulation number passes device indirectly as claimed in claim 1, it is characterized in that, described modulation module (22) is 8-Level CPFSK modulation module, GMSK modulation module.
5. modulation /demodulation number passes device indirectly as claimed in claim 1, it is characterized in that, described demodulation module (27) is 8-Level CPFSK demodulation module, GMSK demodulation module.
6. the indirect modulation /demodulation number as described in claim 1-5 passes a transmission method for device, it is characterized in that, comprises secondary modulation mode and secondary demodulation mode.
7. indirectly modulation /demodulation number passes the transmission method of device as claimed in claim 8, it is characterized in that, described secondary modulation mode comprises:
Steps A 1: described error correction coding module (21) receiving data information, described error correction coding module (21) is carried out error correction coding processing to described data message, is sent to described modulation module (22);
Steps A 2: the data message of described modulation module (22) after to described error correction coding carries out sign map processing, obtains audio base-band modulation signal and is sent to emission filter module (23);
Steps A 3: described emission filter module (23) is carried out shaping filter processing to described audio base-band modulation signal, is sent to described wave-shape amplitude adjustment and emission switch control module (24);
Steps A 4: described wave-shape amplitude adjustment and emission switch control module (24) are carried out amplitude adjustment output to described audio base-band modulation signal.
8. indirectly modulation /demodulation number passes the transmission method of device as claimed in claim 8, it is characterized in that, described secondary demodulation mode comprises:
Step B1: described gain control module (25) audio reception baseband modulation signal, and described audio base-band modulation signal is carried out to signal amplitude adjustment processing, be sent to the described filter module (26) of accepting;
Step B2: the audio base-band modulation signal of described receiving filter module (26) after to described amplitude adjustment carries out filter shape processing, is sent to described demodulation module (27);
Step B3: described demodulation module (27) carries out demodulation process to described audio base-band modulation signal, obtains digital signal and is sent to described error-correcting decoding module (28);
Step B4: described error-correcting decoding module (28) is carried out error-correcting decoding processing to described digital signal, obtains data message output.
9. a ultrashort wave wireless data sending application system, is characterized in that, comprising: ultrashort wave traffic radio station (1), the indirect modulation /demodulation number as described in claim 1-5 pass device (2) and data module (3);
Described ultrashort wave traffic radio station (1), it is connected with described indirect modulation /demodulation number biography device (2), for modulating and send radiofrequency signal and receiving ultrashort wave signal;
Described data module (3), it is connected with described indirect modulation /demodulation number biography device (2), as described user service data terminal, realizes data processing.
10. ultrashort wave wireless data sending application system as claimed in claim 6, is characterized in that, described ultrashort wave traffic radio station (1) comprising:
Audio-frequency module (11), it passes device (2) with described indirect modulation /demodulation number and is connected, described audio base-band modulation signal is carried out to audio signal filtering and amplitude amplification processing, and realize routing switching, the PTT control signal logical process of outside line audio frequency and radio station microphone audio frequency and generate radio station complete machine transmitting keying signal;
Ifd module (12), it is connected with described audio-frequency module (11), described audio base-band modulation signal is carried out to intermediate frequency Modulation and generate modulated intermediate frequency signal, and the ultrashort wave signal receiving is carried out to demodulation, obtains audio base-band modulation signal;
Radio-frequency module (13), it is connected with described ifd module (12), for mixing and the described modulated intermediate frequency signal of excitation, obtains radiofrequency signal;
Transmit-receive switch and antenna (14), it is connected with radio-frequency module (13), for regulating the reiving/transmitting state in described ultrashort wave traffic radio station (1), realizes and sends described radiofrequency signal or receive described ultrashort wave signal.
The transmission method of 11. 1 kinds of ultrashort wave wireless data sending application systems as described in claim 9-10, is characterized in that, comprises transmitted signal mode and signal reception mode.
12. transmission methods of ultrashort wave wireless data sending application system as claimed in claim 11, is characterized in that, described transmitted signal mode comprises:
Step C1: described error correction coding module (21) receives from the data message of described data module (3) output, and described error correction coding module (21) is carried out error correction coding processing to described data message, is sent to described modulation module (22);
Step C2: the data message of described modulation module (22) after to described error correction coding carries out sign map processing, obtains audio base-band modulation signal and is sent to emission filter module (23);
Step C3: described emission filter module (23) is carried out shaping filter processing to described audio base-band modulation signal, is sent to described wave-shape amplitude adjustment and emission switch control module (24);
Step C4: described wave-shape amplitude adjustment and emission switch control module (24) are carried out amplitude adjustment and exported described audio-frequency module (11) to described audio base-band modulation signal;
Step C5: described audio-frequency module (11) carries out routing switching, filtering and amplifies and process described audio base-band modulation signal, is sent to described ifd module (12); The transmitting keying signal that described audio-frequency module (11) generates described radio station complete machine is simultaneously to described transmit-receive switch and antenna (14);
Step C6: described ifd module (12) carries out intermediate frequency Modulation to described audio base-band modulation signal, obtains modulated intermediate frequency signal and is sent to described radio-frequency module (13);
Step C7: described radio-frequency module (13) carries out mixing to described modulated intermediate frequency signal and amplifies and process with excitation, obtains radiofrequency signal;
Step C8: described transmit-receive switch and antenna (14) are adjusted to emission state according to the transmitting keying signal of described radio station complete machine by described ultrashort wave traffic radio station (1), described transmit-receive switch and antenna (14) are sent to spacing wireless channel by described radiofrequency signal.
13. transmission methods of ultrashort wave wireless data sending application system as claimed in claim 11, is characterized in that, described signal reception mode comprises:
Step D1: described transmit-receive switch and antenna (14) are adjusted to accepting state by described ultrashort wave traffic radio station (1), described transmit-receive switch and antenna (14) receive the ultrashort wave signal from spacing wireless channel;
Step D2: described ifd module (12) carries out intermediate frequency demodulation processing to described ultrashort wave signal, obtains audio base-band modulation signal and is sent to described audio-frequency module (11);
Step D3: described audio-frequency module (11) carries out audio frequency output to described audio base-band modulation signal, and described audio base-band modulation signal is sent to described gain control module (25);
Step D4: described gain control module (25) receives the audio base-band modulation signal of described audio-frequency module (11), and described audio base-band modulation signal is carried out to signal amplitude adjustment processing, be sent to the described filter module (26) of accepting;
Step D5: the audio base-band modulation signal of described receiving filter module (26) after to described amplitude adjustment carries out filter shape processing, is sent to described demodulation module (27);
Step D6: described demodulation module (27) carries out demodulation process to described audio base-band modulation signal, obtains digital signal and is sent to described error-correcting decoding module (28);
Step D7: described error-correcting decoding module (28) is carried out error-correcting decoding processing to described digital signal, obtains data message and is sent to data module (3);
Step D8: described data module (3) is carried out subsequent treatment to described data message.
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