CN103905144A - 16-level high-speed narrow-band modem - Google Patents

16-level high-speed narrow-band modem Download PDF

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CN103905144A
CN103905144A CN201210579794.2A CN201210579794A CN103905144A CN 103905144 A CN103905144 A CN 103905144A CN 201210579794 A CN201210579794 A CN 201210579794A CN 103905144 A CN103905144 A CN 103905144A
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module
processing module
data
baseband processing
digital
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CN103905144B (en
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蔡冰昊
项逢智
龚勋
巢献忠
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SHANGHAI XIETONG TECHNOLOGY Inc
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SHANGHAI XIETONG TECHNOLOGY Inc
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Abstract

The invention provides a 16-level high-speed narrow-band modem which includes a data interface module, a base-band processing module and a digital processing module. The base-band processing module is in bidirectional connection with the data interface module and the digital processing module. The base-band processing module performs coding calculation on obtained first data after performing shaking resistance and shaping on first data signals from the data interface module so that a redundant first error-correcting code is generated and then the first data and the first error-correcting code are interweaved and interweaved second data generates a code-element sign according to a 16-level mapping relation and then the code-element sign is sent to the digital processing module; and the base-band processing module also generates third data in a reversed manner through the code-element sign from the digital processing module and performs screening and de-interweaving on third data signals so as to generate forth data and a second error-correcting code in a reversed manner and then the second error-correcting code is used to calculate the accuracy of the forth data and correct repairable error codes in the forth data so that an original sequence of the forth data is restored and forwarded to the data interface module.

Description

16 level high-speed narrow-band modulator-demodulators
Technical field
The present invention relates to wireless narrow band communication field, relate in particular to a kind of 16 level high-speed narrow-band modulator-demodulators.
Background technology
Digital modulation mode is widely used in instant Wireless Data Transmission, in the time that transmission rate improves, corresponding bandwidth also can increase, need variety of protocol support to ensure the accuracy rate of transfer of data, variety of protocol has increased undoubtedly redundant data and has reduced actual transmissions efficiency simultaneously.Existing data transmission system, most GMSK(Gaussian Filtered Minimum Shift Keying that adopt, Gaussian-filtered minimum shift keying) Data Modulation, also there are some to adopt the FSK(Frequency-shift keying of 4 level or 8 level, frequency shift keying), when wherein GMSK speed reaches 9.6kbps and 19.2kbps, its audio bandwidth taking is 4.8kHz and 9.6kHz, exceed common call bandwidth, and 4 level FSK rise to speed at most 9.6kbps in the situation that bandwidth is constant, 8 level FSK also reach at most 19.2kbps.
Industry three remote systems are instantaneities to the demand of transfer of data, and moment mass data transmission necessarily requires the high speed, efficient of data transmission set.The big data quantity here may reach a few KB levels, if transmitted by the transmission rate of the 1.2Kbps in traditional modulation demodulation system or 2.4Kbps, each collection point just needs tens seconds.In the time that a system reaches up to ten thousand collection points, all collection once needs to spend tens hours, and this is that industrial system is intolerable.
Summary of the invention
Technical problem to be solved by this invention is to provide a kind of 16 level high-speed narrow-band modulator-demodulators, can under the prerequisite that does not increase occupied bandwidth, improve message transmission rate.
The present invention is that to solve the problems of the technologies described above the technical scheme adopting be to propose a kind of 16 level high-speed narrow-band modulator-demodulators, comprises data interface module, baseband processing module, digital signal processing module.Described data interface module is for carrying out the signal transfer between external data source and baseband processing module, and described signal transfer comprises insulation blocking and the level translation of interior external circuit.Described baseband processing module respectively with described data interface module, the two-way connection of described digital signal processing module, described baseband processing module comprises anti-shake to the first data-signal from described data interface module, after the fundamental optimum of shaping, to the first data calculating of encoding obtaining, generate the first error correcting code of redundancy, again described the first data and the first error correcting code are interweaved, the second data after interweaving are according to the mapping relations generated code metasymbol of 16 level, then be sent to described digital signal processing module, described baseband processing module is also to the reverse generation of the symbol from described digital signal processing module the 3rd data, and described the 3rd data-signal is screened, deinterleaving, reverse generation the 4th data and the second error correcting code, calculate the accuracy of described the 4th data and correct the error code repaired in described the 4th data by described the second error correcting code, recover the original series of described the 4th data, and be forwarded to described data interface module.
In one embodiment of this invention, 16 level high-speed narrow-band modulator-demodulators also comprise to be controlled and monitoring module, be connected with described baseband processing module is two-way, operation conditions to described baseband processing module is monitored, if operation exception appears in described baseband processing module, described control and monitoring module re-start initialization to described baseband processing module.
In one embodiment of this invention, 16 level high-speed narrow-band modulator-demodulators also comprise data memory module, are connected, to keeping in or permanent storage from described baseband processing module data with described baseband processing module is two-way.
In one embodiment of this invention, described data memory module also carries out program to described baseband processing module and re-writes.
In one embodiment of this invention, 16 level high-speed narrow-band modulator-demodulators also comprise modulus and digital to analog conversion module and analog signal matching module; Described digital signal processing module is to the data processing from described baseband processing module, describe out that analog signal feature offers described modulus and digital to analog conversion module is carried out digital to analog conversion, described digital signal processing module also, to processing from the signal after described modulus and the analog to digital conversion of digital to analog conversion module, restores the data-signal that described baseband processing module can be identified; Described modulus and digital to analog conversion module respectively with described digital signal processing module, described two-way connection of analog signal matching module, signal from described digital signal processing module is carried out to digital-to-analogue conversion, and send the signal after conversion to described analog signal matching module, described modulus and digital to analog conversion module are carried out analog-to-digital conversion to the signal from described analog signal matching module, and send the signal after conversion to described digital signal processing module; Described analog signal matching module and outside two-way connection of radio-frequency module, to carrying out amplification filtering and impedance transformation from the analog signal of described modulus and digital to analog conversion module to mate the requirement of described radio-frequency module, described analog signal matching module carries out impedance transformation and amplification filtering to the signal from described radio-frequency module, makes described radio-frequency module can meet the conversion requirement of described modulus and digital to analog conversion module.
In one embodiment of this invention, 16 level high-speed narrow-band modulator-demodulators also comprise described radio frequency control module, respectively with described baseband processing module, external radio frequency module is two-way is connected, control from baseband processing module and acquisition are converted to the instruction that external radio frequency module can be identified, to convert the instruction that baseband processing module can be identified to from replying of external radio frequency module.
In one embodiment of this invention, the forward error correction coding in described baseband processing module uses RS code.
In one embodiment of this invention, the forward error correction coding in described baseband processing module uses RS(16,12,2) code.
16 level high-speed narrow-band modulator-demodulators of the present invention adopt the modulation and demodulation mode of 16 level, employing amplitude is the modulation system of information carrier, adopt same bandwidth with 4 level and 8 level, increase level capacity to improve message transmission rate, whole scheme has high efficiency and feature cheaply, and execution mode is convenient succinct, is conducive to a large amount of enforcement.
Brief description of the drawings
For above-mentioned purpose of the present invention, feature and advantage can be become apparent, below in conjunction with accompanying drawing, the specific embodiment of the present invention is elaborated, wherein:
Fig. 1 is the theory diagram of the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention;
Fig. 2 is the structural representation of the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention;
Fig. 3 is the check code generative process figure that the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention adopt;
Fig. 4 is the packet structure figure that the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention adopt;
Fig. 5 is the frame assumption diagram that the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention adopt;
Fig. 6 is the synchronous head structure figure that the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention adopt;
Fig. 7 is the symbol synchronization oscillogram that the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention adopt;
Fig. 8 is the frame synchronization structure figure that the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention adopt.
Embodiment
16 level high-speed narrow-band modulator-demodulators of the embodiment of the present invention adopt the modulation and demodulation mode of 16 level, the i.e. modulating mode that employing amplitude is information carrier.
Fig. 1 shows the theory diagram of the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention.Fig. 2 shows the structural representation of the 16 level high-speed narrow-band modulator-demodulators of one embodiment of the invention.Shown in seeing figures.1.and.2, this modulator-demodulator 100 comprises data interface module 102, control and monitoring module 104, baseband processing module 106, data memory module 108, digital signal processing module 110, modulus and digital to analog conversion module 112, analog signal matching module 114, radio frequency control module 116 and power module 118.
In modulator-demodulator 100 outsides, data interface module 102 is connected with external data source 200 is two-way.In modulator-demodulator 100 inside, data interface module 102 is connected with baseband processing module 106 is two-way.Data interface module 102, for carrying out the signal transfer of external data source 200 and baseband processing module 106, comprises insulation blocking and the level translation of interior external circuit.
Control and monitoring module 104 are connected with baseband processing module 106 is two-way, and the operation conditions of baseband processing module 106 is monitored.If there is operation exception in baseband processing module 106, control and monitoring module 104 judge monitoring parameter, when this parameter exceedes after the threshold value of system permission, control and monitoring module 104 force to make baseband processing module 106 to re-start initialization by control channel.
Baseband processing module 106 respectively with data interface module 102, digital signal processing module 110, data memory module 108, radio frequency control module 116 is two-way is connected.Baseband processing module 106 for example, carries out base band calculation process after the first data-signal from data interface module 102 (sending data-signal) being comprised to the fundamental optimum of anti-shake, shaping---coding, be about to the calculating of encoding of the first data, generate the first error correcting code of redundancy, again the first all data and the first error correcting code are interweaved, the second data after interweaving, according to the mapping relations generated code metasymbol of 16 level, are then sent to digital signal processing module 110.Baseband processing module 106 is also for example, to the symbol from digital signal processing module 110 (data-signal that the analog signal receiving generates after analog to digital conversion) reverse generation the 3rd data, and the 3rd data are screened, decoding, the reverse generation of symbol the 3rd data that generate by demodulation, and these the 3rd data are carried out to deinterleaving, recover the 4th data and the second error correcting code, calculate the accuracy of the 4th data and correct the error code repaired in the 4th data according to the second error correcting code again, finally judge the validity of these the 4th data and be forwarded to data interface module 102.All data processings of baseband processing module 106 and storage all complete by data memory module 108.Control and the collection (such as frequency power etc.) of baseband processing module 106 to outside radio-frequency module 300 all completes by radio frequency control module 116.Baseband processing module 106 is controlled the working condition circular of self and monitoring module 104, can be by controlling and monitoring module 104 re-starts initialization to it if occur extremely.
In one embodiment, forward error correction in baseband processing module 106 (Forward Error Correction, FEC) coding can adopt Reed-Solomon code (being called for short RS code).The feature of RS code maximum is to entangle discrete error code, can entangle again the bunchiness error code that strong bursty interference causes, has effectively improved the error performance of transfer of data.The present embodiment adopts the Reed-Solomon code shortening, i.e. RS(16,12,2) code.It adds the error correcting code of 4 bytes in every 12 data bytes, forms the code character of 16 bytes, can correct the error code of 2 bytes.RS(16,12) shortening code be exactly RS(255,251).
Fig. 3 shows the generative process of check code in the cataloged procedure of coding/decoding module according to an embodiment of the invention: with the residue rem (x) that the corresponding polynomial ds (x) of information code character obtains divided by generator polynomial g (x) be exactly the multinomial that check code is corresponding.Polynomial division can be realized with shift register, for RS(16, and 12), the generative process of its check code is shown in Fig. 3.With RS(16,12,2) be example, generator polynomial is: g (x)=x 4+ α 75x 3+ α 249x 2+ α 78x+ α 6.
Baseband processing module 106 interweaves the error correction coding of generation together with initial data, and the present embodiment adopts the short delivery of 3 code characters (3 × 16) to knit, and deinterleaving method is as following table 1 and table 2:
Table 1 is encoded before interweaving
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48
Table 2 is encoded after interweaving
1 17 33 2 18 34 3 19 35 4 20 36 5 21 37 6
22 38 7 23 39 8 24 40 9 25 41 10 26 42 11 27
43 12 28 44 13 29 45 14 30 46 15 31 47 16 32 48
In baseband processing module 106, generate error correction coding and the block diagram that interweaves please refer to the packet structure of Fig. 4.
Baseband processing module 106 by the data that interweaved according to the mapping relations generated code metasymbol of following table 3.
Table 3
Bit 0000 0001 0010 0011 0100 0101 0110 0111
Symbol +15 +13 +11 +9 +7 +5 +3 +1
Bit 1111 1110 1101 1100 1011 1010 1001 1000
Symbol -1 -3 -5 -7 -9 -11 -13 -15
The above-mentioned flow process of baseband processing module 106 contrary operation completes solution error correction.
Data memory module 108 is connected with baseband processing module 106 is two-way, and to keeping in or permanent storage from the data of baseband processing module 106, data memory module 108 can also carry out program to baseband processing module 106 and re-write.
Digital signal processing module 110 is with baseband processing module 106, modulus and digital to analog conversion module 112 is two-way is connected.Digital signal processing module 110 is to processing from the data of baseband processing module 106, describes out that analog signal feature offers modulus and digital to analog conversion module 112 is carried out digital to analog conversion.Digital signal processing module 110 is processed the signal carrying out after analog to digital conversion from modulus and digital to analog conversion module 112, restores the data-signal that baseband processing module 106 can be identified.
Digital signal processing module 110 can adopt the frame structure shown in Fig. 5, comprises synchronous head, frame synchronization, packet n (n<4000) and end mark.At this, synchronous head adopts synchronous head structure shown in Fig. 6, comprise carrier pilot, symbol synchronization, rate information and channel guess value code, carrier pilot adopts sinusoidal wave, symbol synchronization is used Bark pattern (referring to Fig. 7, + 15 ,-15 ,-15 ,+15 ,-15 ,+15), rate information use 4 code elements (+15 ,-15 ,+15 ,-15 represent 38400bps; + 15 ,+15 ,+15 ,-15 represent 19200bps;-15 ,-15 ,+15 ,-15 represent 9600bps; Other combination retains for subsequent use), 20 code elements of channel guess value code employing (+15 ,-3 ,+7 ,+1 ,-7 ,+5 ,-3 ,+7 ,-5 ,-3 ,+1 ,-1 ,+5 ,-7 ,-11 ,+13 ,-3 ,+11 ,-15 ,+5).Frame synchronization adopts frame synchronization structure shown in Fig. 8, comprises each eight of data length information height, separately has two eight as retaining.End mark is two C0.
Digital signal processing module 110 is separated timing and is adopted adaptive channel estimation algorithm, will receive signal automatic calibration to perfect condition, then carries out demodulation.
Digital signal processing module 110 adopts raised cosine low pass filter to realize, and is defined as follows:
H ( f ) = 1 0 &le; f < ( 1 - b ) / ( 2 T ) 0.6 * [ 1 - sin ( &pi;T ( f - 0.6 / T ) / b ) ] ( 1 - b ) / ( 2 T ) &le; f &le; ( 1 + b ) / ( 2 T ) 0 ( 1 + b ) / ( 2 T ) < f
Wherein b=0.2, the time width that T is code element.
Modulus and digital to analog conversion module 112 with digital signal processing module 110, analog signal matching module 114 is two-way is connected.Modulus and digital to analog conversion module 112 are carried out digital-to-analogue conversion to the signal from digital signal processing module 110, and send the signal after conversion to analog signal matching module 114, modulus and digital to analog conversion module 112 are carried out analog-to-digital conversion to the signal from analog signal matching module 114, and send the signal after conversion to digital signal processing module 110.
Analog signal matching module 114 also with modulus and digital to analog conversion module 112, outside two-way connection of radio-frequency module 300.Analog signal matching module 114 is to carrying out the requirement with coupling radio-frequency module 300 of amplification filtering and impedance transformation from the analog signal of modulus and digital to analog conversion module 112.Analog signal matching module 114 carries out impedance transformation and amplification filtering to the signal from radio-frequency module 300, can meet the conversion requirement of modulus and digital to analog conversion module 112.
Radio frequency control module 116 with baseband processing module 106, radio-frequency module 300 is two-way is connected.Radio frequency control module 116 converts to the control from baseband processing module 106 and acquisition the instruction that outside radio-frequency module 300 can be identified to, and replying of the radio-frequency module 300 from outside converted to the instruction that baseband processing module 106 can be identified.
Power module 118 is connected with data interface module 102, control and monitoring module 104, baseband processing module 106, data memory module 108, digital signal processing module 110, modulus and digital to analog conversion module 112, analog signal matching module 114, radio frequency control module 116, for all modules provide the power supply of 5V, 3.3V, 2.5V.
Because the present invention has adopted above technical scheme, the 16 level high-speed narrow-band modulator-demodulators of making are compared with prior art had the following advantages: data frame structure is simple and clear; Increase redundancy encoding code and carry out the error code in forward error correction coding and interweaving encoding reduction transmission, improved the accuracy of transfer of data; Adopt synchronous transfer module balance transmission efficiency; Employing amplitude is the frequency modulation pattern of information carrier, does not increase taking of bandwidth, and whole scheme has high efficiency and feature cheaply, and implements convenient succinctly, is conducive to a large amount of enforcement.
Although the present invention discloses as above with preferred embodiment; so it is not in order to limit the present invention, any those skilled in the art, without departing from the spirit and scope of the present invention; when doing a little amendment and perfect, therefore protection scope of the present invention is worked as with being as the criterion that claims were defined.

Claims (8)

1. 16 level high-speed narrow-band modulator-demodulators, comprise data interface module, baseband processing module, digital signal processing module, wherein,
Described data interface module is for carrying out the signal transfer between external data source and baseband processing module, and described signal transfer comprises insulation blocking and the level translation of interior external circuit;
Described baseband processing module respectively with described data interface module, the two-way connection of described digital signal processing module, described baseband processing module comprises anti-shake to the first data-signal from described data interface module, after the fundamental optimum of shaping, to the first data calculating of encoding obtaining, generate the first error correcting code of redundancy, again described the first data and the first error correcting code are interweaved, the second data after interweaving are according to the mapping relations generated code metasymbol of 16 level, then be sent to described digital signal processing module, described baseband processing module is also to the reverse generation of the symbol from described digital signal processing module the 3rd data, and described the 3rd data-signal is screened, deinterleaving, reverse generation the 4th data and the second error correcting code, calculate the accuracy of described the 4th data and correct the error code repaired in described the 4th data by the second error correcting code, recover the original series of described the 4th data, and be forwarded to described data interface module.
2. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 1, it is characterized in that, also comprise and controlling and monitoring module, be connected with described baseband processing module is two-way, operation conditions to described baseband processing module is monitored, if operation exception appears in described baseband processing module, described control and monitoring module re-start initialization to described baseband processing module.
3. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 1, is characterized in that, also comprise data memory module, are connected, to keeping in or permanent storage from described baseband processing module data with described baseband processing module is two-way.
4. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 3, is characterized in that, described data memory module also carries out program to described baseband processing module and re-writes.
5. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 1, is characterized in that, also comprise modulus and digital to analog conversion module and analog signal matching module;
Described digital signal processing module is to the data processing from described baseband processing module, describe out that analog signal feature offers described modulus and digital to analog conversion module is carried out digital to analog conversion, described digital signal processing module also, to processing from the signal after described modulus and the analog to digital conversion of digital to analog conversion module, restores the data-signal that described baseband processing module can be identified;
Described modulus and digital to analog conversion module respectively with described digital signal processing module, described two-way connection of analog signal matching module, signal from described digital signal processing module is carried out to digital-to-analogue conversion, and send the signal after conversion to described analog signal matching module, described modulus and digital to analog conversion module are carried out analog-to-digital conversion to the signal from described analog signal matching module, and send the signal after conversion to described digital signal processing module;
Described analog signal matching module and outside two-way connection of radio-frequency module, to carrying out amplification filtering and impedance transformation from the analog signal of described modulus and digital to analog conversion module to mate the requirement of described radio-frequency module, described analog signal matching module carries out impedance transformation and amplification filtering to the signal from described radio-frequency module, makes described radio-frequency module can meet the conversion requirement of described modulus and digital to analog conversion module.
6. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 5, it is characterized in that, also comprise described radio frequency control module, respectively with described baseband processing module, external radio frequency module is two-way is connected, control from baseband processing module and acquisition are converted to the instruction that external radio frequency module can be identified, to convert the instruction that baseband processing module can be identified to from replying of external radio frequency module.
7. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 1, is characterized in that, the forward error correction coding in described baseband processing module uses RS code.
8. 16 level high-speed narrow-band modulator-demodulators as claimed in claim 1, is characterized in that, the forward error correction coding in described baseband processing module uses RS(16,12,2) code.
CN201210579794.2A 2012-12-27 2012-12-27 16 level high-speed narrow-band modems Expired - Fee Related CN103905144B (en)

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Publication number Priority date Publication date Assignee Title
CN200969591Y (en) * 2006-08-04 2007-10-31 上海协同科技股份有限公司 Wireless narrowband modem
CN101521788A (en) * 2008-02-25 2009-09-02 徐连彦 Wireless audio frequency and image modem
CN201307865Y (en) * 2008-12-03 2009-09-09 上海协同科技股份有限公司 Moderate-speed wireless narrowband modem
CN102427386A (en) * 2011-09-19 2012-04-25 武汉邮电科学研究院 Polarization shift keying demodulation method and system
CN202261512U (en) * 2011-08-17 2012-05-30 上海协同科技股份有限公司 Eight-level wireless narrow band modem

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN200969591Y (en) * 2006-08-04 2007-10-31 上海协同科技股份有限公司 Wireless narrowband modem
CN101521788A (en) * 2008-02-25 2009-09-02 徐连彦 Wireless audio frequency and image modem
CN201307865Y (en) * 2008-12-03 2009-09-09 上海协同科技股份有限公司 Moderate-speed wireless narrowband modem
CN202261512U (en) * 2011-08-17 2012-05-30 上海协同科技股份有限公司 Eight-level wireless narrow band modem
CN102427386A (en) * 2011-09-19 2012-04-25 武汉邮电科学研究院 Polarization shift keying demodulation method and system

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