CN103763554A - RS decoding module system and method for high-definition-video wireless transmission system based on COFDM - Google Patents

Abstract

The invention discloses an RS decoding module system and method for a high-definition-video wireless transmission system based on COFDM (Code Orthogonal Frequency Division Multiplexing). A valet calculation module is connected with a key-equation solution module. The key-equation solution module is connected with a judgment correction module through a Chien search module and an error-value calculation module. The valet calculation module is connected with a data buffer. The data buffer is connected with the judgment correction module through a register. The key-equation solution module adopts an improved BM algorithm. The system and method have the following advantages: 1. a divide loop is avoided effectively and on the basis that the improved BM algorithm is researched, processing speed is improved effectively while resource occupancy which is not large is increased; 2. a conflict in a wireless transmission process, in which error codes are extremely easy to happen, that rapid and effective transmission of high-quality and highly reliable images, sounds and characters is needed in the high-definition-video wireless transmission system and the like, and error codes are likely to happen in wireless transmission is solved effectively.

Description

The RS decoder module system of the high-definition video wireless transmission system based on COFDM, method

Technical field

The present invention relates to wireless image transmission field, particularly a kind of RS decoder module system, method of the high-definition video wireless transmission system based on COFDM.

Background technology

Coded Orthogonal Frequency Division Multiplexing (COFDM) (Code Orthogonal Frequency Division Multiplexing, COFDM) be a kind of novel data processing technique, rely on its high availability of frequency spectrum, high transmission rate and strong anti-multipath interference performance, in wireless image transmission field, arouse widespread concern.In high-definition video wireless transmission system, the data messages such as high-quality, highly reliable image, sound, word need to be transferred to recipient quickly and efficiently, if while there is spuious Electromagnetic Interference, multipath reflection and impedance mismatch in transmission, receiving terminal will be easy to produce error code, reliability and antijamming capability that this just need to improve transmission system, carrying out effective chnnel coding can effectively address this problem.RS code is as a kind of BCH code with very strong error correcting capability, simultaneously its most powerful and forward error correction of being widely used of a class especially.

In recent years, along with the rise of the cordless communication networks such as GPRS, CDMA, 3G (TD-SCDMA, WCDMA, CDMA2000), OFDM, wireless video transmission system is with its maneuverability, visual pattern, the advantage such as easy to operate, be widely used in the every field such as army individual-soldier operation, public security remote monitoring evidence obtaining, TV programme relay, the monitoring of mine oilfield safety, the environmental monitoring of underground garage supermarket, cell environment monitoring, and become that people realize at a distance, a kind of important means of on-site supervision on a large scale.COFDM technology is high with its transmission rate, antijamming capability is strong, and this makes to realize high-quality realtime graphic and transfer of data becomes possibility at " in high-speed motion " and " non-depending on poker part under ".

Under normal circumstances, wireless transmission channel situation is poor, the situations such as easy as rolling off a log generation error code, communication quality is reduced, this is for requiring high-quality, highly reliable image, sound, the high-definition video wireless transmission system that word rapidly and efficiently transmits, its impact bringing is huge, therefore must adopt the strong and efficient error-correcting code technique of error correcting capability to process information, and conventional parity check code, Hamming code, extended hamming codes etc. all can only remedy a mistake and detect two mistakes, in these transmission systems of having relatively high expectations such as HD video wireless transmission, conventionally having multiple bits or code element makes a mistake, this just needs the coded system that error correcting capability is strong, RS code just in time has significant error correction effect to this type of mistake.Therefore become the emphasis of Recent study.

RS decoding algorithm is generally divided into: syndrome calculating, key equation solving, money search, improper value calculate and five parts of judgement error correction, its core is how to carry out key equation solving, and the method realizing at present is probably divided into: BM algorithm, Euclidean algorithm.Two kinds of algorithms of BM algorithm and Euclidean algorithm are all to adopt the mode of loop iteration to process associated polynomial coefficient, in the hope of solving key equation, Euclidean algorithm carrys out solving equation by finding two polynomial greatest common divisors, its calculating is regular, circular treatment is fairly simple, but complexity is higher, control logic relative complex; And the problem of BM algorithm maximum is the division in algorithm, the current time delay producing is serious in fact.

Summary of the invention

Technical problem to be solved by this invention is, for the deficiencies in the prior art, to provide a kind of RS decoder module system, method of effectively avoiding divide loop, effectively improving the high-definition video wireless transmission system based on C0FDM of processing speed.

For solving the problems of the technologies described above, technical scheme of the present invention is: a kind of RS decoder module system of the high-definition video wireless transmission system based on C0FDM, comprise syndrome computing module, key equation solving module, money search module, improper value computing module, judgement correction module, described syndrome computing module is connected with key equation solving module, described key equation solving module is respectively by money search module, improper value computing module is connected with judgement correction module, described syndrome computing module is connected with data buffer, described data buffer is connected with judgement correction module by register,

Described key equation solving module adopts improves BM algorithm.

Described method comprises the following steps:

A) syndrome calculates;

B) key equation solving, adopts improvement BM algorithm to carry out error location polynomial and improper value polynomial computation;

C) carry out money search;

D) carry out improper value calculating;

E) adjudicate error correction.

In described a step, syndrome calculates, and according to receiving word multinomial R (x), obtains the syndrome of the RS code that can entangle 2t mistake

1≤j≤2t, wherein r _i(1≤i≤n-1) receives word pattern, and α is finite field gf (2 ^m) primitive element, by above syndrome, can form syndrome multinomial $S\left(x\right)=\underset{i-1}{\overset{2t}{\mathrm{\Σ}}}{S}_i{x}^i.$

In described b step, by the method for improving BM algorithm mistake in computation position multinomial λ (x) and improper value multinomial ω (x), be specially,

Initialization: λ ₀(0)=b ₀(0)=1, b _-1(r)=1, k (0)=0, γ (0)=1

λ _i(0)＝b _i(0)＝1，i＝1，2…t

Input: S _i, i=0,1 ... 2t-1

Iteration: for r=0 t0 2t-1 step 1

①δ(r)＝S _r·λ ₀(r)+S _r-1·λ ₁(r)+…+S _r-t·λ _t(r)

②λ _i(r+1)＝γ(r)·λ _i(r)-δ(r)·b _i-1(r) (i＝0，1，2，…，t)

If 3. δ (r) ≠ 0 and k (r) >=0

So

b _i(r+1)＝λ _i(r)(i＝0，1，2，…，t)

γ(r+1)＝δ(r)

k(r+1)＝-k(r)-1

Otherwise

b _i(r+1)＝b _i-1(r)(i＝0，1，2，…，t)

γ(r+1)＝γ(r)

k(r+1)＝k(r)+1

λ _i(2t) i=0,1,2 ..., t is each coefficient of error location polynomial,

①for i＝0 to t-1 step 1

ω _i(2t)＝S _i·λ ₀(2t)+S _i-1·λ ₁(2t)+…+S ₀·λ _t(2t)

ω _i(2t) i=0,1,2 ..., t-1 is polynomial each coefficient of improper value.

In described c step, money searching algorithm is, once by α ⁰, α ..., α ^n-1bring in the error location polynomial λ (x) obtaining, according to α ⁿ=1, α ^-1=α ^n-1if, judgement α ^lbe the root of equation λ (x)=0, can judge α ^n-lit is errors present.

In described d step, use Forney algorithm to carry out improper value calculating.

In described e step, adjudicating error correction method is, α ^lbe the root of equation λ (x)=0, can judge α ^n-lerrors present, by improper value

with reception code word XOR; If α ^lbe not the root of equation λ (x)=0, can judge that this position is error-free, directly output receives code word.

The present invention adopts said structure and method, have the following advantages: 1, the present invention adopts and can effectively avoid the improvement BM algorithm of divide loop to realize the key equation solving in RS decoding, on Improvement BM algorithm basis, when increasing little resource occupation, effectively improve its processing speed; 2, efficiently solve in the wireless transmission process of as easy as rolling off a log generation error code, as needing high-quality, highly reliable image, sound, word, high-definition video wireless transmission system etc. rapidly and efficiently transmits the contradiction that error code easily occurs with wireless transmission, elevator system combination property; 3, the present invention is applicable to the field application such as multi-carrier wireless communication, portable mobile wireless video communication, hand-hold type transmission terminal and DVB-T communication.

Accompanying drawing explanation

Below in conjunction with the drawings and specific embodiments, the present invention is further detailed explanation;

Fig. 1 is structured flowchart of the present invention;

Fig. 2 is the logic diagram that in the present invention, syndrome calculates;

Fig. 3 is that the improvement BM algorithm of key equation solving in the present invention is realized circuit diagram;

Fig. 4 is the logic diagram that in the present invention, errors present calculates;

Fig. 5 represents the calculating of the Forney formula numerator value that in the present invention, improper value calculates;

Fig. 6 represents the calculating of the Forney formula denominator value that in the present invention, improper value calculates;

Fig. 7 represents that in the present invention, Forney formula calculates;

Fig. 8 adjudicates correction module in the present invention to realize circuit diagram;

Fig. 9 is RS decoding simulation result figure;

In Fig. 1,1, syndrome computing module; 2, key equation solving module; 3, money search module; 4, improper value computing module; 5, judgement correction module; 6, data buffer; 7, register.

Embodiment

A kind of RS decoder module system of the high-definition video wireless transmission system based on COFDM as shown in Figure 1, comprise syndrome computing module 1, key equation solving module 2, money search module 3, improper value computing module 4, judgement correction module 5, syndrome computing module 1 is connected with key equation solving module 2, key equation solving module 2 is connected with judgement correction module 5 by money search module 3, improper value computing module 4 respectively, syndrome computing module 1 is connected with data buffer 6, and data buffer 6 is connected with judgement correction module 5 by register 7.Key equation solving module 2 adopts improves BM algorithm.

A RS decoder module system decodes method for high-definition video wireless transmission system based on COFDM, described method comprises the following steps:

A) syndrome calculates;

B) key equation solving, adopts improvement BM algorithm to carry out error location polynomial and improper value polynomial computation;

C) carry out money search;

D) carry out improper value calculating;

E) adjudicate error correction.

As shown in Figure 2, in a step, syndrome calculates, and according to receiving word multinomial R (x), obtains the syndrome of the RS code that can entangle 2t mistake

1≤j≤2t,, wherein r _i(1≤i≤n-1) receives word pattern, and α is finite field gf (2 ^m) primitive element, by above syndrome, can form syndrome multinomial

(wherein:

for XOR,

for multiplying).

As shown in Figure 3, the nucleus module advantage that adopts improvement BM algorithm to realize RS decoding is mainly effectively to avoid division circuit, thereby when reducing resource occupation, the effectively new energy of elevator system.In b step, by the method for improving BM algorithm mistake in computation position multinomial λ (x) and improper value multinomial ω (x), be specially,

Initialization: λ ₀(0)=b ₀(0)=1, b _-1(r)=1, k (0)=0, γ (0)=1

λ _i(0)＝b _i(0)＝1，i＝1，2…t

Input: S _i, i=0,1 ... 2t-1

Iteration: for r=0 to 2t-1 step 1

①δ(r)＝S _r·λ ₀(r)+S _r-1·λ ₁(r)+…+S _r-t·λ _t(r)

②λ _i(r+1)＝γ(r)·λ _i(r)-δ(r)·b _i-1(r) (i＝0，1，2，…，t)

If 3. δ (r) ≠ 0 and k (r) >=0

So

b _i(r+1)＝λ _i(r) (i＝0，1，2，…，t)

γ(r+1)＝δ(r)

k(r+1)＝-k(r)-1

Otherwise

b _i(r+1)＝b _i-1(r) (i＝0，1，2，…，t)

γ(r+1)＝γ(r)

k(r+1)＝k(r)+1

λ _i(2t) i=0,1,2 ..., t is each coefficient of error location polynomial,

①for i＝0 to t-1 step 1

ω _i(2t)＝S _i·λ ₀(2t)+S _i-1·λ ₁(2t)+…+S ₀·λ _t(2t)

ω _i(2t) i=0,1,2 ..., t-1 is polynomial each coefficient of improper value.

As shown in Figure 4, in c step, money searching algorithm is, once by α ⁰, α ..., α ^n-1bring in the error location polynomial λ (x) obtaining, according to α ⁿ=1, α ^-1=α ^n-1if, judgement α ^lbe the root of equation λ (x)=0, can judge α ^n-lit is errors present.

In d step, use Fornev algorithm to carry out improper value calculating.In Fornev algorithm, have wherein α ^lthe root of equation λ (x)=0, as shown in Fig. 5, Fig. 6, Fig. 7.

In e step, adjudicating error correction method is, if α ^lbe the root of equation λ (x)=0, can judge it is α ^n-ltake aim at mistake position, by improper value

with reception code word XOR; If α ^lbe not the root of equation λ (x)=0, can judge that this position is error-free, directly output receives code word.

The present invention utilizes programmable logic device FPGA to build hard-wired RS (204,188) decoding mainly parts such as syndrome computing module, key equation solving module, money search module, improper value computing module, judgement correction module, multiplier, FIFO, ROM, comparator and adders, to consist of.

For verification algorithm computing correctness, native system information source part adopts a string information code data value to be 24 as input, and totally 188 bytes, obtain its 16 check codes by coding circuit and be: 216,227,158,151,43,142,190,199,79,57,100,80,212,232,228,116, we insert 5 mistakes therein, are: 216,227,158,151,43,142,190,199,79,57,101,81,213,233,229,116.From Fig. 9, we can find out, system is correctly corrected 5 place's mistakes of insertion.

On the xc4vlx80-12ff1148 of Virtex4 family device,, placement-and-routing comprehensive by ISE13.4, functional simulation, sequential emulation, RS decoder only takies 2482 slice, and working clock frequency can reach 160.531MHz, and data throughput has reached 601.037Mbps.The data throughout of comparing other implementation method only has 240Mbps, realizes RS decoding in native system, and its processing speed has had obvious lifting.

By reference to the accompanying drawings the present invention is exemplarily described above; obviously specific implementation of the present invention is not subject to the restrictions described above; as long as the various improvement that adopted method design of the present invention and technical scheme to carry out; or directly apply to other occasion without improvement, all within protection scope of the present invention.

Claims (8)

1. the RS decoder module system of the high-definition video wireless transmission system based on COFDM, it is characterized in that: comprise syndrome computing module (1), key equation solving module (2), money search module (3), improper value computing module (4), judgement correction module (5), described syndrome computing module (1) is connected with key equation solving module (2), described key equation solving module (2) is respectively by money search module (3), improper value computing module (4) is connected with judgement correction module (5), described syndrome computing module (1) is connected with data buffer (6), described data buffer (6) is connected with judgement correction module (5) by register (7).

2. the RS decoder module system of a kind of high-definition video wireless transmission system based on COFDM according to claim 1, is characterized in that: described key equation solving module (2) adopts improves BM algorithm.

3. a RS decoder module system decodes method for the high-definition video wireless transmission system based on COFDM according to claim 1 and 2, is characterized in that: described method comprises the following steps:

A) syndrome calculates;

B) key equation solving, adopts improvement BM algorithm to carry out error location polynomial and improper value polynomial computation;

C) carry out money search;

D) carry out improper value calculating;

E) adjudicate error correction.

4. the RS decoder module system decodes method of a kind of high-definition video wireless transmission system based on COFDM according to claim 3, it is characterized in that: in described a step, syndrome calculates, according to receiving word multinomial R (x), obtain the syndrome of the RS code that can entangle 2t mistake

1≤j≤2t, wherein r _i(1≤i≤n-1) receives word pattern, and α is finite field gf (2 ^m) primitive element, by above syndrome, can form syndrome multinomial

5. according to the RS decoder module system decodes method of a kind of high-definition video wireless transmission system based on COFDM described in claim 3 or 4, it is characterized in that: in described b step, by the method for improving BM algorithm mistake in computation position multinomial λ (x) and improper value multinomial ω (x), be specially

Initialization: λ ₀(0)=b ₀(0)=1, b _-1(r)=1, k (0)=0, γ (0)=1

λ _i(0)＝b _i(0)＝1，i＝1，2…t

Input: S _i, i=0,1 ... 2t-1

Iteration: for r=0 to 2t-1 step 1

①δ(r)＝S _r·λ ₀(r)+S _r-1·λ ₁(r)+…+S _r-t·λ _t(r)

②λ _i(r+1)＝γ(r)·λ _i(r)-δ(r)·b _i-1(r) (i＝0，1，2，…，t)

If 3. δ (r) ≠ 0 and k (r) >=0

So

b _i(r+1)＝λ _i(r) (i＝0，1，2，…，t)

γ(r+1)＝δ(r)

k(r+1)＝-k(r)-1

Otherwise

b _i(r+1)＝b _i-1(r)(i＝0，1，2，…，t)

γ(r+1)＝γ(r)

λ _i(2t) i=0,1,2 ..., t is each coefficient of error location polynomial,

④for i＝0 to t-1 step 1

ω _i(2t)＝S _i·λ ₀(2t)+S _i-1·λ ₁(2t)+…+S ₀·λ _t(2t)

ω _i(2t) i=0,1,2 ..., t-1 is polynomial each coefficient of improper value.

6. the RS decoder module system decodes method of a kind of high-definition video wireless transmission system based on COFDM according to claim 5, is characterized in that: in described c step, money searching algorithm is, once by α ⁰, α ..., α ^n-1bring in the error location polynomial λ (x) obtaining, according to α ⁿ=1, α ^-1=α ^n-1if, judgement α ^lbe the root of equation λ (x)=0, can judge α ^n-lit is errors present.

7. the RS decoder module system decodes method of a kind of high-definition video wireless transmission system based on COFDM according to claim 6, is characterized in that: in described d step, use Forney algorithm to carry out improper value calculating.

8. the RS decoder module system decodes method of a kind of high-definition video wireless transmission system based on COFDM according to claim 7, is characterized in that: in described e step, adjudicating error correction method is, α ^lbe the root of equation λ (x)=0, can judge α ^n-lerrors present, by improper value

with reception code word XOR; If α ^lbe not the root of equation λ (x)=0, can judge that this position is error-free, directly output receives code word.

Images