CN2672967Y - Radio frequency extension digital three net blend transmission device - Google Patents
Radio frequency extension digital three net blend transmission device Download PDFInfo
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- CN2672967Y CN2672967Y CN 200320119558 CN200320119558U CN2672967Y CN 2672967 Y CN2672967 Y CN 2672967Y CN 200320119558 CN200320119558 CN 200320119558 CN 200320119558 U CN200320119558 U CN 200320119558U CN 2672967 Y CN2672967 Y CN 2672967Y
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Abstract
The utility model relates to a radio frequency extension digital three net blend transmission device, comprising a main transmitter and a main receiver matched with the main transmitter. In the main transmitter, a first compressing and encoding circuit, a first multiplex circuit, a first frequency extending circuit and a first transmitting circuit are orderly matched to accomplish the image, voice and data transmission from the main transmitter to the main receiver, and a first receiving circuit, a first frequency de-extending circuit, a first de-multiplex circuit and a first decompressing and decoding circuit are orderly matched to accomplish the voice and data transmission from the main receiver to the main transmitter. The main receiver is provided with a corresponding circuit to accomplish the bidirectional transmission. Wherein, the main transmitter can transmit an image, a voice and a data to the main receiver which only transmits the voice and the data to the main transmitter. The corresponding radio frequency extension three net blend transmission system can be composed through the above main transmitter and the main receiver so as to realize the real-time voice, image and data transmission and raise the working efficiency of the emergent processing of the public security system on site.
Description
Technical field
The utility model relates to field of wireless transmission, more particularly, relates to a kind of wireless communication technology, Image Compression and network technology of having fully utilized, and can be used for the wireless frequency expansion numeral integration of three networks transmitting device of images, voice and data.
Background technology
In the actual application of public security system, regular meeting runs into the situation that need utilize image, these three kinds of information real-time communications of voice-and-data; For example need the voice that the commanding in the rear center is transmitted in time to link up at the scene, need again the realtime graphic and the voice messaging at scene are delivered to command centre, or other auxiliary image scenes being delivered to operation center so that implementation decision, on-the-spot simultaneously relevant data message also needs to carry out alternately with the inner powerful data information network of public security.In these information communication processes, the level security of transmittance process that also must guarantee information.
The existing transmitting device of public security system all has the unicity problem of message transmission, usually can only transmitting voice information.Existing trunking communication net can solve the problem of single voice transfer preferably, and this also is the main commander's information transmission mode of present public security system; By existing public telephone network, mobile communications network just can solve single data communication problem preferably, but because of non-public security system dedicated network level security not strong; What original internal proprietary wireless image transmission system that is adapted to the public security system use adopted is the analog form transmission, one side occupied channel broader bandwidth, level security also is difficult to be guaranteed on the other hand, and the state decree regulation is also being phased out this transmission means simultaneously.
The utility model content
Above-mentioned defective at prior art, the utility model will solve existing transmitting device, the transmitting device of public security special use particularly, institute's information transmitted is more single, the problem of poor reliability, provide a kind of reliability height, fail safe good, simultaneously images, voice-and-data transmission of Information device.
The scheme that the utility model solves its technical problem is, a kind of wireless frequency expansion numeral integration of three networks transmitting device is provided, and comprises master transmitter and the main receiver that cooperates with it,
In described master transmitter, comprise first image interface that is used to receive from the picture signal of outside input, first data-interface that is used for first speech interface of input and output voice signal and is used for inputoutput data information; Comprise that also picture signal and voice signal to input carry out the first compressed encoding circuit that compressed encoding is handled, the compressed voice that the described first compressed encoding circuit is exported picture signal and carry out first multiplex circuit of multiplexing process with synthetic circuit-switched data stream from the data that described first data-interface is imported, the data flow that described first multiplex circuit is exported is carried out first spectrum spreading circuit of spread processing, and, first radiating circuit that the signal after the spread processing is launched;
In described main receiver, comprise second image interface that is used for to outside output image signal, second data-interface that is used for second speech interface of input and output voice signal and is used for inputoutput data information; Also comprise second receiving circuit that receives signal that described master transmitter sends, what the signal that described second receiving circuit is exported separated that spread spectrum handles second separates spectrum spreading circuit, separating signal that spectrum spreading circuit exports to described second carries out demultiplexing and handles to restore the second demultiplexing circuit of a circuit-switched data and one tunnel Ya Suoyuyin picture signal, and, the compressed voice that the described second demultiplexing circuit is exported picture signal decompress to restore the second decompress(ion) decoding circuit of original image signal and voice signal, the described original image signal that restores, voice signal and data output to described second image interface respectively, second speech interface and second data-interface.
The wireless frequency expansion numeral integration of three networks transmitting device of such scheme can be realized by image, the voice-and-data transmission of master transmitter to main receiver; For the ease of linking up and management, also need transmit control corresponding data or voice messaging to master transmitter by main receiver, so, in the utility model,
Also comprise in the described main receiver: the voice signal from described second speech interface input is carried out the second compressed encoding circuit that compressed encoding is handled, the compressed voice signal that the compressed encoding circuit is exported and carry out second multiplex circuit of multiplexing process with synthetic circuit-switched data stream from the data that described second data-interface is imported, the data flow that described second multiplex circuit is exported is carried out second spectrum spreading circuit of spread processing, and, second radiating circuit that the signal after the spread processing is launched;
Also comprise in the described master transmitter: first receiving circuit that receives signal that described master transmitter sends, what the signal that described first receiving circuit is exported separated that spread spectrum handles first separates spectrum spreading circuit, separating signal that spectrum spreading circuit exports to described first carries out demultiplexing and handles to restore the first demultiplexing circuit of a circuit-switched data and one road compressed voice signal, and, be used for the compressed voice signal that described demultiplexing circuit is exported is decompressed to restore the first decompress(ion) decoding circuit of primary speech signal, described initial data that restores and voice signal output to described first data-interface and first speech interface respectively.
In the utility model, comprise the modulation circuit, frequency changer circuit, amplifying circuit, bandwidth-limited circuit and the emission match circuit that connect successively in described first, second radiating circuit respectively; Comprise the reception match circuit, amplifying circuit, bandwidth-limited circuit, frequency changer circuit and the demodulator circuit that connect successively in described first, second receiving circuit respectively; Emission match circuit in described first radiating circuit and shared first antenna of the reception match circuit in first receiving circuit; Emission match circuit in described second radiating circuit and shared second antenna of the reception match circuit in second receiving circuit.
For further being convenient to transmit image, the voice-and-data that main receiver is received, in described main receiver, also comprise with described second output of separating spectrum spreading circuit being connected, being used for separating the image that contains data and compression that spectrum spreading circuit exports and the data flow of voice signal outputs to outside network interface with described second.Described network interface be ethernet interface circuit and or the wireless lan interfaces circuit.
In the utility model, the described first compressed encoding circuit is the MPEG-4 condensing encoder, and the described second decompress(ion) decoding circuit is a MPEG-4 decompress(ion) decoder, is used to realize corresponding image compression encoding and decompress(ion) decoding function.
Compared with prior art, wireless frequency expansion numeral integration of three networks transmitting device of the present utility model has the following advantages:
(1) can transmit multiple information simultaneously, its master transmitter can transmit the data flow of being made up of image, voice-and-data simultaneously to main receiver;
(2) adopted the wireless frequency expansion transmission technology, antijamming capability is strong, the high communication quality, and level security is good, and diffracting power is strong, can support high speed mobile transmission;
(3) main receiver is furnished with network interface, can directly be connected with network, carries out remote image transmission, can realize the Network Transmission of multimedia messages such as digital picture;
(4) multiple information flow concentration of transmissions, the stability of a system, device integrated level improve, and the integrated application cost reduces;
(5) information flow multiplexing transmission has improved the degree of integration of information, saves transmission bandwidth;
(6) interface standard connects simply, and is easy to use, saved existing numerous, the line complicated problems of many information terminals connecting interface.
Description of drawings
The utility model is described in further detail below in conjunction with drawings and Examples, in the accompanying drawing:
Fig. 1 is the theory diagram of master transmitter in preferred enforcement of the utility model;
Fig. 2 is the theory diagram of the main receiver that cooperates with master transmitter shown in Figure 1;
Fig. 3 is the block diagram of the first compressed encoding circuit in preferred enforcement of the utility model;
Fig. 4 is second decompress(ion) decoding circuit and the block diagram corresponding with the first compressed encoding circuit;
Fig. 5 is the block diagram of the second compressed encoding circuit in preferred enforcement of the utility model;
Fig. 6 is first decompress(ion) decoding circuit and the block diagram corresponding with the second compressed encoding circuit.
Embodiment
In the wireless frequency expansion of the present utility model numeral integration of three networks transmitting device, the principle of master transmitter as shown in Figure 1, the principle of main receiver with matching is as shown in Figure 2.Master transmitter is wherein made removable pattern usually, allows the user can utilize the place that the corresponding vehicles or manpower mode are carried to be needed; The main receiver of Pei Heing then is installed in neighbouring or far-end control command centre with it, master transmitter can corresponding one or more main receivers, main receiver also can corresponding one or more master transmitters, thereby form corresponding wireless image, voice, data transmission system, make between on-the-spot and the commanding in the rear control centre, and between the on-the-spot different azimuth, place, can realize real-time image, voice, transfer of data, thereby improve the means of message transmission greatly, increase work efficiency.
As can be seen from Figure 1, three interfaces are arranged in the master transmitter, i.e. first image interface 101, first speech interface 102 and first data-interface 103; Wherein first image interface, 101 one-way only operations receive only the outside picture signal of importing; First speech interface 102 and 103 two-way operations of first data-interface both can receive outside input, also can export to the outside.
(wherein TX represents to send the direction of arrow from Fig. 1 as can be seen, RX represents to receive), in master transmitter, cooperate successively by first radiating circuit in the first compressed encoding circuit 104, first multiplex circuit 105, first spectrum spreading circuit 106 and the top frame of broken lines, finish by image, the voice-and-data transmission of master transmitter to main receiver.And separate spectrum spreading circuit 116, the first demultiplexing circuit 114 and the first decompress(ion) decoding circuit 113 by first receiving circuit in the lower dotted line frame, first and cooperate successively, finish by the voice-and-data transmission of main receiver to master transmitter.Wherein be used for separating spectrum spreading circuit 116 spreading code is provided to first spectrum spreading circuit 105 and first by spreading code unit 115.
As can be seen from Figure 1, comprise modulation circuit 107, frequency changer circuit 108, amplifying circuit 109, bandwidth-limited circuit 110 and the emission match circuit 111 that connects successively in first radiating circuit; Comprise the reception match circuit 121, amplifying circuit 120, bandwidth-limited circuit 119, frequency changer circuit 118 and the demodulator circuit 117 that connect successively in first receiving circuit; Emission match circuit 111 and reception match circuit 121 shared first antennas 112.
With first radiating circuit is example, modulation circuit 107 wherein is used for the signal after the spread processing is modulated into intermediate-freuqncy signal, it is high-frequency signal that frequency changer circuit 108 is used for the intermediate-freuqncy signal frequency-conversion processing after the modulation, amplifying circuit 109 is used for described high-frequency signal is amplified, bandwidth-limited circuit 110 is used for the high-frequency signal of amplifying circuit output is carried out bandpass filtering treatment, outwards launches by the emission match circuit 111 and first antenna 112 then.The course of work of first receiving circuit is then just opposite, no longer describes in detail herein.
As can be seen from Figure 2, three interfaces are arranged also in the master transmitter, i.e. second image interface 201, second speech interface 202 and second data-interface 203; Wherein second image interface, 201 one-way only operations receive only the outside picture signal of importing; Second speech interface 202 and 203 two-way operations of second data-interface both can receive outside input, also can export to the outside.
The direction of arrow from Fig. 2 as can be seen, in master transmitter, separate spectrum spreading circuit 216, the second demultiplexing circuit 214 and the second decompress(ion) decoding circuit 213 by second receiving circuit in the lower dotted line frame, second and cooperate successively, finish by image, the voice-and-data transmission of master transmitter to main receiver.And cooperate successively by second radiating circuit in the second compressed encoding circuit 204, second multiplex circuit 205, second spectrum spreading circuit 206 and the top frame of broken lines, finish by the voice-and-data transmission of main receiver to master transmitter.Wherein separate spectrum spreading circuit 216 to second spectrum spreading circuit 205 and second spreading code is provided by 215 of spreading code unit.As can be seen from Figure 2, for further being convenient to the transmission of picture signal, at the network interface 222 that second output of separating spectrum spreading circuit 216 also connects, can be used for second separate the image that contains data and compression that spectrum spreading circuit exports, the data flow of voice signal outputs to the outside.
As can be seen from Figure 2, comprise modulation circuit 207, frequency changer circuit 208, amplifying circuit 209, bandwidth-limited circuit 210 and the emission match circuit 211 that connects successively in second radiating circuit; Comprise the reception match circuit 221, amplifying circuit 220, bandwidth-limited circuit 219, frequency changer circuit 218 and the demodulator circuit 217 that connect successively in second receiving circuit; Emission match circuit 211 wherein and reception match circuit 221 shared second antennas 212.
By Fig. 1 and Fig. 2 as can be seen, master transmitter can be to main receiver images, voice-and-data; And main receiver is only to master transmitter transferring voice and data.So the first compressed encoding circuit 104 will carry out the compressed encoding processing to image and voice signal; And first separate 113 of the decoding circuits of contracting and compressed voice signal is carried out decompress(ion) decoding handle.On the contrary, 204 in the second compressed encoding circuit carries out compressed encoding to voice signal and handles; And second separate the decoding circuit 213 that contracts and will carry out decompress(ion) decoding to the image of compression and voice signal and handle.
In the utility model, first, second radiating circuit, each part in first, second receiving circuit all are ripe prior aries, and therefore following is introduced other several circuit.
One, the first compressed encoding circuit 104 and the second decompress(ion) decoding circuit 213
The first compressed encoding circuit 104 and the second decompress(ion) decoding circuit 213 are finished the compressed encoding and the decompress(ion) decoding of image and voice signal respectively.Because the containing much information of picture signal, the transmission bandwidth that takies memory capacity and requirement is big especially, therefore at first will carry out efficient compressed encoding to it, to reach the image compression of extremely low code check, guarantees image loss of information not substantially in transmission course simultaneously.In addition, also require image compression can not be too responsive to error code, can adapt to the wireless channel transmission high bit-error, the time become problem such as multipath, and cost can not be too high.
As shown in Figure 3 and Figure 4, can adopt existing MPEG-4 image compression coding and decoding technology (MPEG, promptly Motion Picture Experts Group is the compression standard of bigger live image of a kind of compression ratio and sound), and adopt corresponding ASIC (application-specific integrated circuit (ASIC)) chip.Adopt the TriMediaPNX1311EH chip of Philips company to finish MPEG4 coding and decoding function in the present embodiment, and adopt SAA7111 image A/D chip that picture signal is converted to digital signal, adopt SAA7121 to carry out image D/A conversion and format conversion, become the output of the TV signal of the NTSC/PAL standard that meets international standard, to realize analog image collection, digitlization and complicated extensive compressed encoding computing.Its image resolution ratio can reach 352 * 288 pixel/frame (CIF form), and speed can reach for 25 frame/seconds, and real-time Transmission dynamic image respond well do not have " animation " sensation, and clear picture, " action " agility can satisfy the needs that scene of the accident realtime graphic transmits.
As shown in Figure 3 and Figure 4, because of the first compressed encoding circuit except the compressed encoding of finishing video image, also to finish the compressed encoding of audio signal; Correspondingly, the second decompress(ion) decoding circuit also will be finished the decompress(ion) decoding of audio signal except the decompress(ion) decoding of finishing video image.So also adopted audio compression coding chip 320AIC121 in the present embodiment.The utility model sound intermediate frequency is supported multiple compress mode, comprises Standard PC M (A leads, μ lead), can select the compress mode of GSM6.10 when requiring lower code check, with further reduction utilized bandwidth.
As shown in Figure 5 and Figure 6, only finish the compressed encoding of audio signal at the second compressed encoding circuit; Correspondingly, the first decompress(ion) decoding circuit is only finished the decompress(ion) decoding of audio signal.That present embodiment adopts is audio compression coding chip 320AIC121.
Two, spectrum spreading circuit and separate spectrum spreading circuit
When information is transmitted, require to have higher communication quality under wireless channel conditions; Particularly under the abominable geography in the scene of the accident, electromagnetic environment, require communication port to have stronger anti-interference and ability anti-fading, anti-multipath.Common non-spreading channel is difficult to satisfy above-mentioned requirements.Therefore, adopt existing spread spectrum technic in the present embodiment, carry out band-spread wireless digital in 336～344MHz frequency range, and adopt high-speed figure to handle (DSP) technology and the integrated design of FPGA, to realize high performance spectrum spreading circuit design, its circuit design integrated level height, good reliability.Channel speed can carry out flexible configuration as requested from 512Kbps～1Mbps.
Adopt direct sequence spread spectrum skill in the present embodiment, in the spectrum spreading circuit of master transmitter, the signal that will send expands on the very wide frequency band with two-forty pseudo noise code (spreading code); Separating in the spectrum spreading circuit of main receiver, with identical pseudo noise code the signal of receiving is carried out relevant treatment, recover original signal.
After adopting above-mentioned spectrum spreading circuit, interference power can be expanded to very wide frequency band and get on, the interference power of entering signal frequency band be reduced greatly, thereby make whole device have stronger antijamming capability; Because the signal spectrum after the direct sequence spread spectrum is very wide, the sub-fraction decline is little to the influence of whole signal, so the anti fading performance of whole device is good, particularly the performance of anti-frequency selective fading is fine; Simultaneously, the correlation properties of direct sequence spread spectrum skill pseudo-code, make system can be under environment with a varied topography such as city operate as normal, the performance that anti-multipath disturbs is fine; In addition, can make whole device have very strong disguise and the anti-ability of intercepting and capturing, have stronger level security.
Three, network interface
Master transmitter that this is practical and the effective propagation path between the main receiver are about 10 kilometers, in some major accident, on-the-spot realtime graphic information need be sent to farther place, all advantages based on the Internet, best bet is to carry out remote transmission by existing network, realize the Network Transmission of digitized image, can adopt the IP technology of the present most widely used network transmission protocol, the code stream that image compression encoding is formed adapts to interface and the protocol architecture thereof that Network Transmission requires.For this reason, adopt the Ethernet interface 10BASE/100BASE-T of present extensive use in the present embodiment, for example utilize the RTL8019AS of Realtek company that physical layer interface is provided, network upper-layer protocol family content is then realized by dsp software, can finish the digital network transmission that realizes image.Simultaneously, also adopted the wireless lan interfaces circuit in the present embodiment, main receiver can directly be connected with wireless lan (wlan), the image information of receiving to long-range transmission by WLAN (wireless local area network).
Like this, can carry out the real time remote transmission of scene of the accident image by means of existing computer network system, as the transmission of carrying out image file by LAN (Local Area Network) (LAN), wide area network (WAN) and the Internet (Internet) with browse, the remote transmission problem is converted into the image file (or saying Streaming Media) after the compression, be that image compression encoder can directly insert Intranet, even Internet, authorized users (for example controlling command centre) can also can long-range online be carried out picture browsing and on-site supervision in the online of the office of this locality.
Claims (8)
1, a kind of wireless frequency expansion numeral integration of three networks transmitting device comprises master transmitter and the main receiver that cooperates with it, it is characterized in that,
Comprise in the described master transmitter:
Be used to receive first image interface from the picture signal of outside input,
First speech interface that is used for the input and output voice signal,
First data-interface that is used for inputoutput data information,
Picture signal and voice signal to input carry out the first compressed encoding circuit that compressed encoding is handled,
The compressed voice that the described first compressed encoding circuit is exported picture signal and carry out first multiplex circuit of multiplexing process with synthetic circuit-switched data stream from the data that described first data-interface is imported,
The data flow that described first multiplex circuit is exported is carried out first spectrum spreading circuit of spread processing,
And, first radiating circuit that the signal after the spread processing is launched;
Comprise in the described main receiver:
Be used for second image interface to outside output image signal,
Second speech interface that is used for the input and output voice signal,
Second data-interface that is used for inputoutput data information,
Receive second receiving circuit of signal that described master transmitter sends,
What the signal that described second receiving circuit is exported separated that spread spectrum handles second separates spectrum spreading circuit,
Separate signal that spectrum spreading circuit exports to described second and carry out demultiplexing and handle restoring the second demultiplexing circuit of a circuit-switched data and one tunnel Ya Suoyuyin picture signal,
And, the compressed voice that the described second demultiplexing circuit is exported picture signal decompress restoring the second decompress(ion) decoding circuit of original image signal and voice signal,
The described original image signal that restores, voice signal and data output to described second image interface, second speech interface and second data-interface respectively.
2, wireless frequency expansion numeral integration of three networks transmitting device according to claim 1 is characterized in that,
Also comprise in the described main receiver:
Voice signal from described second speech interface input is carried out the second compressed encoding circuit that compressed encoding is handled,
The compressed voice signal that the compressed encoding circuit is exported and carry out second multiplex circuit of multiplexing process with synthetic circuit-switched data stream from the data that described second data-interface is imported,
The data flow that described second multiplex circuit is exported is carried out second spectrum spreading circuit of spread processing,
And, second radiating circuit that the signal after the spread processing is launched;
Also comprise in the described master transmitter:
Receive first receiving circuit of signal that described master transmitter sends,
What the signal that described first receiving circuit is exported separated that spread spectrum handles first separates spectrum spreading circuit,
Separate signal that spectrum spreading circuit exports to described first and carry out demultiplexing and handle restoring the first demultiplexing circuit of a circuit-switched data and one road compressed voice signal,
And, be used for the compressed voice signal that described demultiplexing circuit is exported is decompressed to restore the first decompress(ion) decoding circuit of primary speech signal, described initial data that restores and voice signal output to described first data-interface and first speech interface respectively.
3, wireless frequency expansion numeral integration of three networks transmitting device according to claim 2 is characterized in that,
Comprise the modulation circuit, frequency changer circuit, amplifying circuit, bandwidth-limited circuit and the emission match circuit that connect successively in described first, second radiating circuit respectively;
Comprise the reception match circuit, amplifying circuit, bandwidth-limited circuit, frequency changer circuit and the demodulator circuit that connect successively in described first, second receiving circuit respectively;
Emission match circuit in described first radiating circuit and shared first antenna of the reception match circuit in first receiving circuit;
Emission match circuit in described second radiating circuit and shared second antenna of the reception match circuit in second receiving circuit.
4, according to each described wireless frequency expansion numeral integration of three networks transmitting device among the claim 1-3, it is characterized in that, in described main receiver, also comprise with described second output of separating spectrum spreading circuit being connected, being used for separating the image that contains data and compression that spectrum spreading circuit exports and the data flow of voice signal outputs to outside network interface described second.
5, wireless frequency expansion according to claim 4 numeral integration of three networks transmitting device is characterized in that, described network interface be ethernet interface circuit and or the wireless lan interfaces circuit.
6, wireless frequency expansion numeral integration of three networks transmitting device according to claim 4 is characterized in that the described first compressed encoding circuit is the MPEG-4 condensing encoder; The described second decompress(ion) decoding circuit is a MPEG-4 decompress(ion) decoder.
7, wireless frequency expansion numeral integration of three networks transmitting device according to claim 4 is characterized in that described first, second spectrum spreading circuit is the direct sequence spread spectrum circuit, and it is that direct sequence is separated spectrum spreading circuit that described first, second separated spectrum spreading circuit.
8, wireless frequency expansion numeral integration of three networks transmitting device according to claim 4 is characterized in that the operating frequency of described master transmitter and main receiver is the 336-344MHz frequency range.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200320119558 CN2672967Y (en) | 2003-12-18 | 2003-12-18 | Radio frequency extension digital three net blend transmission device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN 200320119558 CN2672967Y (en) | 2003-12-18 | 2003-12-18 | Radio frequency extension digital three net blend transmission device |
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| CN2672967Y true CN2672967Y (en) | 2005-01-19 |
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| CN 200320119558 Expired - Fee Related CN2672967Y (en) | 2003-12-18 | 2003-12-18 | Radio frequency extension digital three net blend transmission device |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103312421A (en) * | 2013-07-08 | 2013-09-18 | 高铭 | Safe refuging wireless ground penetrating communication system for mine |
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2003
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103312421A (en) * | 2013-07-08 | 2013-09-18 | 高铭 | Safe refuging wireless ground penetrating communication system for mine |
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