CN102957656A - System information sending and receiving method and device in digital audio broadcasting system - Google Patents

Abstract

The invention discloses a system information sending and receiving method and device in a digital audio broadcasting system. The method comprises the following steps of: when in sending, performing CRC (cyclic redundancy check) coding and channel coding on the system information to generate a coding bit stream; performing bit interleaving and constellation mapping on the coding bit stream to obtain a continuous pilot frequency including the system information; multiplexing a continuous pilot frequency signal with other signal elements of the system to obtain a frequency-domain signal of an orthogonal multiplexing structure according to a carrier allocation method stipulated by a frequency spectrum mode; converting the frequency-domain signal into a time-domain signal for sending; when in receiving, converting the time-domain signal into a frequency-domain signal; extracting the continuous pilot frequency including the system information from an effective carrier of the frequency-domain signal according to the position stipulated by the frequency spectrum mode; obtaining an estimated value of the system information through de-mapping, de-interleaving and channel decoding; and judging the correctness of the system information by use of CRC decoding, and outputting the system information. The method and device disclosed by the invention can improve the transmission robustness on the basis of guaranteeing the transmission efficiency of the system information.

Description

The sending and receiving methods of system information and device in the digital audio broadcast system

Technical field

The present invention relates to the DAB Technology field, relate in particular to sending and receiving methods and the transceiver of system information in a kind of digital audio broadcast system.

Background technology

Digital audio broadcast system has the characteristics such as availability of frequency spectrum height, wide coverage, programme content be abundant.In order to provide better service quality and user to experience, digital audio broadcasting supports to comprise the multiple business pattern of data service and audio service usually.

Normal operation plays vital effect to system for the transmission of system information in the digital audio broadcast system (being also referred to as control information) and reception.Generally include the modulation coding mode of main business in the system information, the important contents such as allocation of carriers mode in case mistake appears in system information, may cause the connection failure of whole system.On the other hand, the demodulation code of system information must be finished fast, and is very high to requirement of real-time, if system information can not in time solve, can have influence on whole system equally.Therefore, the transmission of the system information of effective robust (being robustness) and method of reseptance are one of keys in the digital audio broadcast system design.In the digit broadcasting systems such as present DVB-T, DRM, HD-Radio and CMMB, all selected comparatively efficiently system information transmissions scheme, but its robustness can not be guaranteed, therefore can not satisfy the requirement of digital audio broadcast system.

Summary of the invention

In view of this, main purpose of the present invention is to provide sending and receiving methods and the transceiver of system information in a kind of digital audio broadcast system, on the basis of the efficiency of transmission that guarantees system information, improves the robustness of its transmission.

Technical scheme of the present invention is achieved in that when sending the system information that comprise the steps: A, will need to send is carried out cyclic redundancy check (CRC) coding and chnnel coding processing successively, produces coded bit stream; B, described coded bit stream carried out Bit Interleave is processed and constellation mapping is processed, obtain comprising the continuous pilot of system information; C, according to the allocation of carriers mode of spectrum mode regulation, other signal element of described continuous pilot signal and system is multiplexed to the frequency-region signal of orthogonal multiplex structure; D, described frequency-region signal is converted into time-domain signal for transmission.

Wherein in step C, carry out further comprising: according to system frame structure, generate the continuous pilot signal with repeated characteristic before the described multiple connection operation.In described continuous pilot signal with repeated characteristic, system information is transmitted take a logic subframe as unit, and in a logic subframe, system information symbol repeats to transmit secondary.Described continuous pilot signal in the distribution mode on carrier wave and the symbol is: from left to right second subband of each effective subband and the system information symbol of a logic subframe of first subband carrying are placed on respectively on the continuous carrier wave according to spectrum mode.

The method further strengthens the power of described continuous pilot signal.

When receiving, comprise the steps: a, time-domain signal is converted to frequency-region signal; B, according to the position of spectrum mode regulation, from effective carrier wave of described frequency-region signal, extract the continuous pilot that comprises system information; The estimated value that mapping, deinterleaving and channel-decoding obtain system information is separated in c, utilization; D, utilize CRC decoding that the correctness of system information is judged, according to judged result output system information.

Among the step b, the concrete utilization comprises that the deversity scheme of frequency diversity and time domain diversity carries out input to the continuous pilot of described effective carrier wave, and extracts continuous pilot.

The dispensing device of system information in the digital audio broadcast system of the present invention, comprise: the cyclic redundancy check (CRC) encoder, be used for input system information, carry out the cyclic redundancy check (CRC) coding, produce and comprise that the systematic code of system information and check information exports to channel encoder; Channel encoder is used for the systematic code according to input, searches out corresponding coding codeword in codeword set, produces to comprise that the coded bit stream of redundant information exports to bit interleaver; Bit interleaver is for according to pre-defined rule the coded bit stream of input being resequenced and exporting to constellation mapper; Constellation mapper is used for the coded bit stream mapping of input is obtained continuous pilot; Multiplexer is used for the allocation of carriers mode according to the spectrum mode regulation, and other signal element multiple connection of described continuous pilot signal and system is in the same place, and the frequency-region signal that produces the orthogonal multiplex structure is exported to the time and frequency zone converter; The time and frequency zone converter is used for the input frequency domain signal is transformed to time-domain sampling for transmission.

This dispensing device further comprises: reproducer, be arranged between described constellation mapper and the multiplexer, and be used for according to system frame structure, generation has the continuous pilot signal of repeated characteristic and exports to multiplexer.

The receiving system of system information in the digital audio broadcast system of the present invention comprises: the time-the frequency converter, be used for time-domain signal is converted to frequency-region signal and outputs to signal detector; Signal detector, according to the position of spectrum mode regulation, extraction comprises the continuous pilot of system information and exports to de-mapping device from effective carrier wave of described frequency-region signal; De-mapping device is used for described continuous pilot solution mapping and output encoder bit stream to deinterleaver; Deinterleaver is used for described coded bit stream is carried out deinterleaving and outputs to decoder; Channel decoder is used for input signal is carried out channel-decoding, obtains the estimated value of system information and exports to the CRC decoder; The CRC decoder is used for the correctness of the system information of input is judged the output judged result.

Compared with prior art, system information of the present invention sends and receives scheme under the condition that does not need extra bandwidth, namely guaranteed the efficiency of transmission of system information, improved on this basis again the robustness of system information transmissions, and the present invention also can support flexibly spectrum mode and multifrequency point collaborative work, thereby can significantly improve the frequency diversity gain of ofdm system, reduce error rate of system, increase coverage or reduce transmitting power.In addition, the present invention can also repeat transmitting system information in continuous pilot signal, therefore can improve the probability that system information is correctly decoded, the power of the continuous pilot of bearing system information can also be strengthened, thereby further improve the robustness of system information.The present invention can be widely used in each digital audio broadcasting field such as satellite audio broadcast, terrestrial wireless audio broadcasting, the hand-held audio broadcasting in ground, especially can be applicable to adopt the multicarrier system of Fourier conversion, Walsh conversion or wavelet transformation.

Description of drawings

Fig. 1 is the schematic diagram of the dispensing device of system information in the digital audio broadcast system of the present invention;

Fig. 2 is the schematic diagram of the receiving system of system information in the digital audio broadcast system of the present invention;

Fig. 3 is the baseband frequency spectrum schematic diagram of ofdm communication system of the present invention;

Fig. 4 is CRC shift register block diagram of the present invention;

Fig. 5 is the schematic diagram of encoder for convolution codes of the present invention;

Fig. 6 is QPSK signal constellation and mapping of the present invention;

Fig. 7 is the module frame chart that frequency-region signal of the present invention generates;

Fig. 8 is the sub-carrier indices schematic diagram of transmission mode 1 of the present invention and 3 o'clock;

Sub-carrier indices schematic diagram when Fig. 9 is transmission mode 2 of the present invention;

Figure 10 is the embodiment schematic diagram of the receiving system information that receives of the present invention.

Embodiment

The present invention is further described in more detail below in conjunction with drawings and the specific embodiments.

The described digital audio broadcast system of the embodiment of the invention is the digital audio broadcast system based on Coded Orthogonal Frequency Division Multiplexing (COFDM) (COFDM).

Fig. 1 is the schematic diagram of the dispensing device of system information in the digital audio broadcast system of the present invention.Referring to Fig. 1, this dispensing device comprises:

The Cyclic Redundancy Check encoder is used for input system information, carries out the cyclic redundancy check (CRC) coding, produces to comprise that the systematic code of system information and check information exports to channel encoder;

Channel encoder is used for the systematic code according to input, searches out corresponding coding codeword in codeword set, produces to comprise that the coded bit stream of redundant information exports to bit interleaver;

Bit interleaver is for according to pre-defined rule the coded bit stream of input being resequenced and exporting to constellation mapper;

Constellation mapper is used for the coded bit stream mapping of input is obtained continuous pilot; Search out the corresponding symbol of every section bit stream in constellation space after the bit stream of input is cut apart, produce symbol sebolic addressing and export to multiplexer;

Multiplexer, be used for the allocation of carriers mode according to the spectrum mode regulation, other signal element (such as load, discrete guide-frequency signal) multiple connection of described continuous pilot signal and system is in the same place, and the frequency-region signal that produces the orthogonal multiplex structure is exported to the time and frequency zone converter;

The time and frequency zone converter is used for the input frequency domain signal is transformed to time-domain sampling for transmission.

Robustness for further safeguards system communication, the present invention can further include a reproducer, be arranged between described constellation mapper and the multiplexer, be used for according to system frame structure, generation has the continuous pilot signal (symbol sebolic addressing that namely has repeated characteristic) of repeated characteristic and exports to multiplexer.

Fig. 2 is the schematic diagram of the receiving system of system information in the digital audio broadcast system of the present invention.Referring to shown in Figure 2, this receiving system comprises:

The time-the frequency converter, be used for time-domain signal is converted to frequency-region signal and outputs to signal detector;

Signal detector, according to the position of spectrum mode regulation, extraction comprises the continuous pilot of system information and exports to de-mapping device from effective carrier wave of described frequency-region signal; The concrete utilization comprises that the deversity scheme of frequency diversity and time domain diversity carries out input to the continuous pilot of described effective carrier wave herein, and extracts continuous pilot.

De-mapping device is used for described continuous pilot solution mapping and output encoder bit stream to deinterleaver;

Deinterleaver is used for described coded bit stream is carried out deinterleaving and outputs to decoder;

Channel decoder, be used for input signal is carried out channel-decoding, employing comprises the decoding FEC that transmits based on message of SOVA and BCJR, and the Sum-LLR method decodes to continuous pilot, obtains the estimated value of system information and exports to the CRC decoder

The CRC decoder is used for the correctness of the system information of input is judged the output judged result.

Based on Fig. 1 and the described sending and receiving device of Fig. 2, the below introduces the method for sending and receiving of system information in the digital audio broadcast system of the present invention.

The sending method of system information of the present invention comprises:

Step 101, the system information that will need to send are carried out CRC coding and chnnel coding processing successively, produce coded bit stream.

In this step, specifically adopt the CRC coding to produce the systematic code that comprises system information and check information; Described chnnel coding searches out corresponding coding codeword namely according to this systematic code in codeword set, produce the coded bit stream that comprises redundant information.And described chnnel coding is processed and is specially the convolutional encoding processing.

Step 102, described coded bit stream carried out Bit Interleave is processed and constellation mapping is processed, obtain comprising the continuous pilot of system information.

Described Bit Interleave is processed and is comprised that specifically block interleaved is processed and convolutional interleave is processed, and according to pre-defined rule coded bit stream is resequenced; Described constellation mapping is processed and is specially the processing of QPSK mapping mode, searches out the corresponding symbol of every section bit stream in constellation space after bit stream is cut apart, and produces the symbol sebolic addressing of system information.

Step 103, with the continuous pilot of this symbol sebolic addressing as system information, according to the allocation of carriers mode of spectrum mode regulation, other signal element of described continuous pilot signal and system is multiplexed to the frequency-region signal of orthogonal multiplex structure.In a kind of optimal way, carry out also can further comprising: according to system frame structure, generate the continuous pilot signal with repeated characteristic before the described multiple connection operation.

Step 104, described frequency-region signal is converted into time-domain signal for transmission.

Corresponding, at receiving terminal, the method for reseptance of system information comprises in the described digital audio broadcast system:

Step 201, time-domain signal is converted to frequency-region signal.

Step 202, according to the position of spectrum mode regulation, from effective carrier wave of described frequency-region signal, extract the continuous pilot that comprises system information.Concrete, utilize to comprise that the deversity scheme of frequency diversity and time domain diversity carries out input to the continuous pilot of described effective carrier wave, and extract continuous pilot.

The estimated value that mapping, deinterleaving and channel-decoding obtain system information is separated in step 203, utilization.Described channel-decoding is specially: the decoding FEC based on the message transmission that comprises SOVA and BCJR.

Step 204, utilize CRC decoding that the correctness of system information is judged, according to judged result output system information.

System frame structure of the present invention comprises 4 layers of superframe, frame, subframe and OFDM symbols.The present invention is divided into three transmission modes.In transmission mode 1, each superframe is divided into 4 frames, and each frame is divided into 4 subframes, and each subframe is divided into 57 OFDM symbols, and each symbol has 242 effective carrier waves.First OFDM symbol of each subframe is used for system synchronization and demodulation preliminary treatment as beacon, and other 56 OFDM symbols then comprise load, scattered pilot, continuous pilot and virtual subnet carrier wave.In transmission mode 2, each superframe is divided into 4 frames, and each frame is divided into 4 subframes, and each subframe is divided into 112 OFDM symbols, and each symbol has 122 effective carrier waves.First OFDM symbol of each subframe is as beacon, and other 111 OFDM symbols then comprise load, scattered pilot, continuous pilot and virtual subnet carrier wave.In transmission mode 3, each superframe is divided into 4 frames, and each frame is divided into 4 subframes, and each subframe is divided into 62 OFDM symbols, and each symbol has 242 effective carrier waves.Wherein, first OFDM symbol of each subframe is as beacon, and other 61 OFDM symbols then comprise load, scattered pilot, continuous pilot and virtual subnet carrier wave.Each OFDM symbol by the protection interval as prefix to reduce the OFDM intersymbol interference.Transmission mode 1 is identical with the subcarrier spacing of transmission mode 3, but protects gap length different, and the subcarrier spacing of transmission mode 2 is twices of aforementioned two kinds of patterns.Define unit interval T=1/816000 second, the system parameterss such as subcarrier spacing, mark space, insured interval are as shown in table 1:

Table 1

The subband that ofdm signal is 100kHz by maximum 8 nominal bandwidth forms.Spectrum mode has been stipulated the quantity of subband, and the position of effective subband and empty subband.In the partial frequency spectrum pattern, whole subcarriers are empty subcarrier in first subband of some effective subband or second subband.Fig. 3 is the baseband frequency spectrum schematic diagram of ofdm communication system of the present invention, referring to Fig. 3, and 0 Frequency point respective signal center frequency point, the i.e. position of OFDM symbol subcarrier 0 wherein.

Spectrum mode among the present invention has two classes, i.e. category-A spectrum mode and category-B spectrum mode.Wherein the category-A spectrum mode comprises 8 subbands, and subband nominal frequency is ± (i*100+50) kHz, i=0,1,2,3; The category-B spectrum mode comprises 7 subbands, and subband nominal frequency is the integral multiple of 100kHz, namely ± i*100kHz, i=0,1,2,3.In system information, the absolute value of the difference on the frequency of the center frequency point of a subband and signal center's frequency can be described with 3 bits, i.e. subband nominal frequency position, table 2 has provided the corresponding relation of describing bit in subband nominal frequency position and the system information.

Bit value

Subband nominal frequency position

s 0s 1s 2
		000	0kHz
100	50kHz
		010	100kHz
110	150kHz
		001	200kHz
101	250kHz
		011	300kHz
111	350kHz

Table 2

System information described in the digital audio broadcast system of the present invention is comprised of 48 bits, comprises the information such as multifrequency point collaborative work information, spectrum mode index, coding, modulation, CRC coding.

The bit b of system information ₀b ₁... b ₄₇Definition see the following form shown in 3:

Bit	Information is described
		b 0	The indication of multifrequency point cooperative work mode
b 1～b 9	Next subframe multifrequency point collaborative work frequency
		b 10～b 12	Current subband nominal frequency
b 13～b 18	The spectrum mode index
		b 19～b 20	The position of current physical layer signal frame
b 21～b 22	Current subframe position
		b 23～b 24	The sub-frame allocation mode
b 25～b 26	The modulation system of business description information
		b 27～b 28	The modulation system of business datum
b 29～b 30	The hierarchical modulation indication of business datum
		b 31	The coding of business datum adopts the evenly indication of protection
b 32～b 33	The LDPC encoder bit rate of business datum
		b 34～b 35	The LDPC encoder bit rate of business datum
b 36～b 41	Keep Rfa
		b 42～b 47	The CRC check position

Table 3

Each bit in the described table 3 is defined as follows:

b ₀: the indication of multifrequency point cooperative work mode, 0 expression multifrequency point collaborative work; The non-multifrequency point collaborative work of 1 expression.In system information, need 1 bit to indicate current subframe whether to support the multifrequency point collaborative work, if support, also need 9 extra working frequency points than the next subframe in indication Contemporary Digital radio station.The multifrequency point cooperative work can significantly improve the frequency diversity gain of ofdm system, thereby reduces error rate of system, increases coverage or reduces transmitting power.The multifrequency point collaborative work is a plurality of Traffic Channels to be interweaved at a plurality of frequencies as the basis take frequency hopping, alternately take channel predetermined separately, the stronger selectivity of actual propagation channel tool on frequency that forms is again by encoding this frequency diversity that is selectively converted to.Frequency hopping is take subframe as unit, realizes take superframe as the cycle.

b ₁～b ₉: the frequency of next subframe multifrequency point collaborative work makes b ₁～b ₉The signless integer of expression (b wherein ₁Be highest significant position) be I, then next subframe multichannel collaborative work frequency is (87+0.05*I) MHz, when non-multifrequency point collaborative work, b ₁～b ₉Be 1.

b ₁₀～b ₁₂: current subband nominal frequency, definition sees Table 2, b ₁₀～b ₁₂S in the successively corresponding table 2 ₀～s ₂

b ₁₃～b ₁₈: the spectrum mode index can represent 39 kinds of possible spectrum modes.

b ₁₉～b ₂₀: the position of current physical layer signal frame in a superframe, 00 expression the 1st frame; 01 expression the 2nd frame; 10 expressions the 3rd frame; 11 expressions the 4th frame.

b ₂₁～b ₂₂: the position of current subframe in a physical layer signal frame, 00 expression the 1st subframe; 01 expression the 2nd subframe; 10 expressions the 3rd subframe; 11 expressions the 4th subframe.

b ₂₃～b ₂₄: the sub-frame allocation mode, 00 keeps; 01 expression sub-frame allocation mode 1; 10 expression sub-frame allocation modes 2; 11 expression sub-frame allocation modes 3.

b ₂₅～b ₂₆: the modulation system of business description information, 00 expression QPSK; 01 expression 16QAM; 10 expression 64QAM; 11 keep.

b ₂₇～b ₂₈: the modulation system of business datum, 00 expression QPSK; 01 expression 16QAM; 10 expression 64QAM; 11 keep.

b ₂₉～b ₃₀: the hierarchical modulation indication of business datum, hierarchical modulation is not supported in 00 expression; 01 expresses support for hierarchical modulation and α=1; 10 express support for hierarchical modulation and α=2; 11 express support for hierarchical modulation and α=4.

b ₃₁: the coding of business datum adopts the evenly indication of protection, and even protection is not adopted in 0 expression; Evenly protection is adopted in 1 expression.

b ₃₂～b ₃₃: the LDPC encoder bit rate of business datum, 00 table 1/4 encoder bit rate; 01 expression, 1/3 encoder bit rate; 10 expressions, 1/2 encoder bit rate; 11 expressions, 3/4 encoder bit rate.

b ₃₄～b ₃₅: the LDPC encoder bit rate of business datum, 00 expression, 1/4 encoder bit rate; 01 expression, 1/3 encoder bit rate; 10 expressions, 1/2 encoder bit rate; 11 expressions, 3/4 encoder bit rate.

When non-layered is modulated, if the encoder bit rate of the business datum when adopting evenly protection is by b ₃₂～b ₃₃Indication, b ₃₄～b ₃₅Keep; If adopt inhomogeneous protection, then the encoder bit rate of business datum obtains from professional descriptor, b ₃₂～b ₃₅Keep.When hierarchical modulation, the encoder bit rate of the business datum of high protection is by b ₃₂～b ₃₃Indication, the encoder bit rate of the business datum of low protection is by b ₃₄～b ₃₅Indication.

b ₃₆～b ₄₁: keep Rfa, be left in the future expansion and use.

b ₄₂～b ₄₇: the CRC check position.

In above-mentioned steps 101, order is carried out CRC to the 0th to the 41st system information and is calculated in the table 3 the 42nd to the 47th CRC check position.The generator polynomial of CRC is: G ₆(x)=x ⁶+ x ⁵+ x ³+ x ²+ x+1, its corresponding shift register block diagram is seen Fig. 4, the initial value of shift register is 111111.

In above-mentioned steps 101, it is 7 1/4 convolution code that described chnnel coding adopts constraint length, the encoder of convolution code as shown in Figure 5, corresponding octal system generator polynomial is: 133,171,145,133, the shift register initial value be entirely " 0 ".Convolution coder is with input bit a _i, i=0,1 ..., T-1 generated codeword x _{0, i}, x _{1, i}, x _{2, i}, x _{3, i}, i=0,1,2 ..., T+5, this code word is defined as follows:

$x_{0,i}=a_i\⊕a_{i-2}\⊕a_{i-3}\⊕a_{i-5}\⊕a_{i-6};$

$x_{1,i}=a_i\⊕a_{i-1}\⊕a_{i-2}\⊕a_{i-3}\⊕a_{i-6};$

$x_{2,i}=a_i\⊕a_{i-1}\⊕a_{i-4}\⊕a_{i-6};$

$x_{3,i}=a_i\⊕a_{i-2}\⊕a_{i-3}\⊕a_{i-5}\⊕a_{i-6};$

When i do not belong to set 0,1,2 ..., during T-1}, a _iBe zero.Each code word

Ordering is the female code word U of a serial successively, is expressed as: U=(u ₀, u ₁, u ₂..., u _i..., u _4T+23), wherein, $u_i=x_{R\left(\frac{i}{4}\right),Q\left(\frac{i}{4}\right)},i=\mathrm{0,1,2},...,4T+23.$

System information is carried out convolutional encoding.For the original position replacement linear feedback shift register of business description information in each logical frame, for the original position replacement linear feedback shift register of system information in each logic subframe.The low level of system information bit streams is front, i.e. b ₀Front.

In above-mentioned steps 102, coded bit stream carries out constellation mapping in the QPSK mode, and Fig. 6 has provided the QPSK signal constellation and mapping.Coded bit stream is inputted in the constellation mapper in the preferential mode of MSB, and mapper produces symbol sebolic addressing by every group of corresponding sequence number output symbol of two bits.

Fig. 7 is the module frame chart that frequency-region signal of the present invention generates, as shown in Figure 7, and in above-mentioned steps 103, with described symbol sebolic addressing as continuous pilot, with load and scattered pilot multiple connection, and add the virtual subnet carrier wave, generate the OFDM frequency-region signal with orthogonal multiplex structure.

Among the present invention, described system information is transmitted take a subframe as unit.According to system frame structure, continuous pilot also need to repeat to send the probability that is correctly decoded to improve system information at a plurality of symbols.

The distribution mode of continuous pilot on carrier wave and symbol is as follows:

The system information of a logic subframe comprises 108 system information symbol.108 system information symbol that the system information of a logic subframe of from left to right second subband of each effective subband (when its subcarrier during not entirely for empty subcarrier) and first subband (when its subcarrier during not entirely for empty subcarrier) being carried according to spectrum mode comprises are placed on respectively on the continuous carrier wave.

The structure line number is 4*S _N, columns is N _v* N _IThe subcarrier matrix M, the line number of subcarrier matrix and columns all since 1 the counting.Element in the subcarrier matrix is divided into system information elements, scattered pilot element and data element.Be S with the subcarrier matrix by from top to bottom, from left to right being divided into line number _N, columns is N _vSubmatrix M _{S, t}, namely $M=\left[\begin{array}{cccc}{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HDA00002022282200022.png,HDA00002022282200031.png"\; state="\{\{state\}\}">M</figure-callout>}}_{\mathrm{1,1}}& {\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HDA00002022282200022.png,HDA00002022282200031.png"\; state="\{\{state\}\}">M</figure-callout>}}_{\mathrm{1,2}}& ...& {\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="HDA00002022282200022.png,HDA00002022282200031.png"\; state="\{\{state\}\}">M</figure-callout>}}_{1,N_I}\\ M_{\mathrm{2,1}}& M_{2,2}& ...& M_{2,N_I}\\ M_{\mathrm{3,1}}& M_{\mathrm{3,2}}& ...& M_{3,N_I}\\ M_{\mathrm{4,1}}& M_{\mathrm{4,2}}& ...& M_{4,N_I}\end{array}\right],$ Wherein

m _{A, b}(a=1,2 ... S _N, b=1,2 ..., N _v) element of expression in the submatrix.

Table 5 has provided system information elements and has been positioned at M _{S, t}The position that is listed as in every delegation, table 6 have provided that system information symbol takies M under each transmission mode _{S, t}The position of row.

In a logic subframe, 108 system information symbol of system information repeat twice, for example, in the transmission mode 1, M _{S, t}The 1st～27 row in 108 system information symbol of position place system information of table 5 appointment, the assigned address of the 28th～54 row is also placed same system information symbol.

Table 5

Table 6

When transmission mode 1, M _{S, t}55～56 row in fill the system information symbol that 1～2 row is placed on the position of table 5 appointment, when transmission mode 2, M _{S, t}109～111 row in fill the system information symbol that 1～3 row is placed on the position of table 5 appointment, when transmission mode 3, M _{S, t}55～61 row in fill the system information symbol that 1～7 row is placed on the position of table 5 appointment.

Fig. 8 is the sub-carrier indices schematic diagram of transmission mode 1 and 3 o'clock.Sub-carrier indices schematic diagram when Fig. 9 is transmission mode 2.Referring to Fig. 8 and Fig. 9, shown in the power of continuous pilot all be enhanced 3dB, to reduce inter-carrier interference to the impact of continuous pilot, further improve the robustness of system information.

Figure 10 is the embodiment schematic diagram of the receiving system information that receives of the present invention.Referring to Figure 10, at receiving terminal, specifically comprise:

Time-domain signal is converted to frequency-region signal; Extract continuous pilot according to the spectrum mask assigned position.Utilize channel estimating and equalizer that described continuous pilot is carried out demodulation (namely separating mapping), obtain including the demodulation symbol (being soft information) of diversity gain; Carry out again the duplication code decoding, with the soft information addition of restituted signal, obtain separating more reliably mapping result (namely strengthening soft information); Should separate again mapping result through in input SOVA or the BCJR channel decoder after the deinterleaving, generation comprises the soft information of control (being the soft information of system) of system information and CRC check information, after this is controlled soft information and adjudicate, output system information provides the judgement of system information correctness on the other hand by the CRC decoding on the one hand.If provide the indication that system information is made mistakes, then need again the system information of next superframe to be decoded again, until provide the correct indication of system information.

The above only is preferred embodiment of the present invention, and is in order to limit the present invention, within the spirit and principles in the present invention not all, any modification of making, is equal to replacement, improvement etc., all should be included within the scope of protection of the invention.

Claims (13)

1. the sending method of system information in the digital audio broadcast system is characterized in that this sending method comprises:

A, the system information that will need to send are carried out cyclic redundancy check (CRC) coding and chnnel coding processing successively, produce coded bit stream;

B, described coded bit stream carried out Bit Interleave is processed and constellation mapping is processed, obtain comprising the continuous pilot of system information;

C, according to the allocation of carriers mode of spectrum mode regulation, other signal element of described continuous pilot signal and system is multiplexed to the frequency-region signal of orthogonal multiplex structure;

D, described frequency-region signal is converted into time-domain signal for transmission.

2. sending method according to claim 1 is characterized in that, carries out further comprising: according to system frame structure, generate the continuous pilot signal with repeated characteristic before the described multiple connection operation in step C.

3. sending method according to claim 2 is characterized in that, the method further strengthens the power of described continuous pilot signal.

4. sending method according to claim 2 is characterized in that, among the step C, in described continuous pilot signal with repeated characteristic, system information is transmitted take a logic subframe as unit, and in a logic subframe, system information symbol repeats to transmit secondary.

5. sending method according to claim 2 is characterized in that, among the step C, the distribution mode of described continuous pilot signal on carrier wave and symbol is:

From left to right second subband of each effective subband and the system information symbol of a logic subframe of first subband carrying are placed on respectively on the continuous carrier wave according to spectrum mode.

6. sending method according to claim 1 is characterized in that,

Chnnel coding described in the steps A is processed and is specially the convolutional encoding processing;

Bit Interleave described in the step B is processed and is comprised that specifically block interleaved is processed and convolutional interleave is processed;

Constellation mapping described in the step B is processed and is specially the processing of QPSK mapping mode.

7. according to claim 1 to 6 described methods, it is characterized in that described digital audio broadcast system is for adopting the multicarrier system of Fourier conversion, Walsh conversion or wavelet transformation.

8. the method for reseptance of system information in the digital audio broadcast system is characterized in that this method of reseptance comprises:

A, time-domain signal is converted to frequency-region signal;

B, according to the position of spectrum mode regulation, from effective carrier wave of described frequency-region signal, extract the continuous pilot that comprises system information;

The estimated value that mapping, deinterleaving and channel-decoding obtain system information is separated in c, utilization;

D, utilize CRC decoding that the correctness of system information is judged, according to judged result output system information.

9. method of reseptance according to claim 8 is characterized in that, among the step b, the concrete utilization comprises that the deversity scheme of frequency diversity and time domain diversity carries out input to the continuous pilot of described effective carrier wave, and extracts continuous pilot.

10. method of reseptance according to claim 8 is characterized in that, channel-decoding is specially described in the step c: the decoding FEC based on the message transmission that comprises SOVA and BCJR.

11. the dispensing device of system information in the digital audio broadcast system is characterized in that this dispensing device comprises:

The cyclic redundancy check (CRC) encoder is used for input system information, carries out the cyclic redundancy check (CRC) coding, produces to comprise that the systematic code of system information and check information exports to channel encoder;

Channel encoder is used for the systematic code according to input, searches out corresponding coding codeword in codeword set, produces to comprise that the coded bit stream of redundant information exports to bit interleaver;

Bit interleaver is for according to pre-defined rule the coded bit stream of input being resequenced and exporting to constellation mapper;

Constellation mapper is used for the coded bit stream mapping of input is obtained continuous pilot;

Multiplexer is used for the allocation of carriers mode according to the spectrum mode regulation, and other signal element multiple connection of described continuous pilot signal and system is in the same place, and the frequency-region signal that produces the orthogonal multiplex structure is exported to the time and frequency zone converter;

The time and frequency zone converter is used for the input frequency domain signal is transformed to time-domain sampling for transmission.

12. dispensing device according to claim 11 is characterized in that, this dispensing device further comprises:

Reproducer is arranged between described constellation mapper and the multiplexer, is used for according to system frame structure, produces to have the continuous pilot signal of repeated characteristic and export to multiplexer.

13. the receiving system of system information in the digital audio broadcast system is characterized in that this receiving system comprises:

The time-the frequency converter, be used for time-domain signal is converted to frequency-region signal and outputs to signal detector;

Signal detector, according to the position of spectrum mode regulation, extraction comprises the continuous pilot of system information and exports to de-mapping device from effective carrier wave of described frequency-region signal;

De-mapping device is used for described continuous pilot solution mapping and output encoder bit stream to deinterleaver;

Deinterleaver is used for described coded bit stream is carried out deinterleaving and outputs to decoder;

Channel decoder is used for input signal is carried out channel-decoding, obtains the estimated value of system information and exports to the CRC decoder;

The CRC decoder is used for the correctness of the system information of input is judged the output judged result.

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