CN100531164C

CN100531164C - Time inverse-interlacing memory reducing method for DMB signal receiver

Info

Publication number: CN100531164C
Application number: CNB2004100679146A
Authority: CN
Inventors: 姜益善; 高禹锡
Original assignee: Shanghai LG Electronics Co Ltd
Current assignee: Shanghai LG Electronics Co Ltd
Priority date: 2004-11-05
Filing date: 2004-11-05
Publication date: 2009-08-19
Anticipated expiration: 2024-11-05
Also published as: CN1770749A

Abstract

This invention relates to digital multimedia broadcasting Signal receiver and especially to time cross memory reduce method. The signal receiver of this invention and its cross memory reduce method uses the data with crossed time in the receiver to process repeated crossed process memory, wherein the above memory only uses parts for segment process.

Description

The wrong memory reducing method of the time reciprocal cross of DMB signal receiver

Technical field

The present invention relates to the invention of digital multimedia broadcasting; Particularly, the technology of required memory size in the anti-interleaver of time of minimizing digital multimedia broadcast signal receiver.

Background technology

Generally, the numberization of broadcasting has been brought no small impact to existing analog radio broadcasting, and has caused the arrival in digital radio broadcasting epoch.In addition, be not only existing voice radio broadcast service, comprise that also data transmit and the digital multimedia broadcasting (Digital Multimedia Broadcasting:DMB) of multimedia service all becomes possibility.Digital multimedia broadcasting transmits the noise on the channel and distorts influence owing to overcome, and not only transmission efficiency is than higher, but also various multimedia service can be provided.

The digital multimedia of the domestic employing of Korea S broadcasting (DMB) now is the surface wave radio broadcasting standard Eureka-147 digital audio broadcasting (DAB) based on Europe; And, in order to improve the performance of multimedia broadcasting, appended the RS code (Reed-Solomon Code) and the convolutional interleaving encoding device (Convolutional Interleaver) that can overcome the group wrong (Burst Error) that may take place on the transmission channel.

Above-mentioned two modules that are added are applicable to DAB integral body (Ensemble) input signal in sender unit; And in the movable signal reception environment, also can provide low relatively error rate, can realize Video service.

The transmission channel of above-mentioned DMB broadcasting is wireless mobile receiving channels, not only the scope of received signal (Amplitude) can the time become (Time-Varying), and because Doppler's diffusion (DopplerSpreading) of received signal frequency spectrum (Spectrum) also can take place in the influence of mobile receiver.

In addition, DMB transmission signal is little more a lot of than existing analog radio broadcast signal strength; In the more serious channel environment of (Fading) phenomenon such as decay such as picture centre of the city etc., if consider movable signal receiving system such as automobile, the signal strength signal intensity of actual reception signal is very little.

Consider the signal transmission/reception in such channel environment, the DMB load mode is based on orthogonal frequency multiplexing (Orthogonal Frequency Division Multiplexing), in time zone and frequency field to signal interlock (Interleaving) handle, can stablize like this and transmit the mistake that is taken place in the channel.

Then, the DMB receiver receives received signal to greatest extent in above-mentioned abominable signal receiving circumstance, can revisal transmit mistake.In addition, consider this factor of movable signal receiving terminal machine, utilize limited expense to embody receptivity to greatest extent, the core of DMB signal receiver formation that Here it is.

In addition, in order to realize the randomization of ensemble mistake, must carry out time interleaving and handle.

Here, so-called above-mentioned time interleaving refers to, preserve data within a certain period of time after, different with the reception of data order, transmit data in any order.

Fig. 1 is the time interleaving display list according to common DMB specification.

At first, the time interleaving method of being formulated in the DMB specification, be saved in the data in 16 frames in the memory after, carry out randomization according to step-by-step negate rule shown in Figure 2.

Equally, receiving side signal is handled for this is recovered, and must the elapsed time reciprocal cross miss journey; And, still need memory in order to preserve the data in 16 frames.

With reference to Fig. 1, be applicable to the time interleaving in the DMB specification, from time r to r+15 till, be equivalent to carry out in time of 16 frames the form that data transmit.

Here, a _{R, i}I the data (sample) of the time r that refers to.

By the data that are transmitted in the time r before staggered, along with the variation of i (modulo) value from 0 to 15, according to the step-by-step negate rule among Fig. 2, originally data a _{R, i}Interlocked and be a _{R ', i}

Like this, time reciprocal cross fault reason is by the reverse process of said process, from a _{R ', i}Obtain a _{R, i}

According to above-mentioned DMB specification, there are 55296 samples in the frame, therefore the memory size of general anti-interleaver of time when its soft decision (soft decision) forms 4 bits, needs the memory of 16 * 55296 * 4 bits; But the memory of real time reciprocal cross mistake only uses dark part among Fig. 1 in 16 frames, so remainder is obsolete (idle) part, has caused the waste of memory.

Summary of the invention

Purpose of the present invention is exactly in order to solve above-mentioned variety of problems, provide and reduce required memory size in the interior time reciprocal cross mistake of DMB signal receiver, and reduce the wrong memory reducing method of DMB signal receiver time reciprocal cross of required door size in the DMB signal receiving chip ASICization.

In order to achieve the above object, adopted in the DMB signal receiver required memory in the process of being carried out reciprocal cross fault reason by the data of staggered certain hour; And the part that above-mentioned memory only uses reality is carried out fragment (segment) processing.

Best, above-mentioned memory possesses, and can to preserve size (size) be 15 fragment 0 to size is 8 the fragment 14 positions storage space of 120 samples altogether.

And above-mentioned fragment adopts the mould pivot residual (modulo) of corresponding size, is that unit carries out time reciprocal cross fault reason with the fragment.Above-mentioned multiple being staggered in the process of reading, the value of first reading and saving in the wrong memory of time reciprocal cross, and export by anti-interleaver; In the ablation process, in the wrong memory of the reciprocal cross of identical address when reading, write the input content of anti-interleaver.

As above tell about, the present invention can reduce the memory size in the most important resource in half chip; Therefore, can reduce the size of door simultaneously, make the chip of DMB signal receiver be able to ASICization, be made into single-chip (one chip).

Description of drawings

Fig. 1 is the time interleaving display list that meets common digital multimedia broadcasting specification;

Fig. 2 is the display list of step-by-step negate (bit reverse) rule of time interleaving table among Fig. 1;

Fig. 3 is the display module figure of digital multimedia broadcast signal receiver among the present invention;

Fig. 4 is the wrong memory construction displayed map of digital multimedia broadcast signal receiver time reciprocal cross among the present invention.

* accompanying drawing major part symbol description *

11: antenna 12: tuner

13: automatic gain controller (AGC) 14:A/D transducer

15: mode detection apparatus 16:I/Q distributor

17: signal Synchronization device 18:OFDM demodulator

19: the anti-interleaver 20 of frequency: channel divider 1

21:FIC decipher 22:FIC data decryption device

23: anti-interleaver 24 of time: convolution decipher

25: energy descrambler 26: channel divider 2

27: audio/data decipher 28: the anti-interleaver of convolution

29:RS decipher 30: decryption of video device

Embodiment

With reference to the accompanying drawings, formation in the embodiment of the invention and effect are described.

Fig. 3 is the module map of DMB signal receiver among the present invention.

With reference to Fig. 3, the DMB signal receiver comprises following parts: receive the antenna 11 that has transmitted broadcast singal; Be converted to the tuner 12 of required intermediate frequency (Intermediate Frequency) passband (Pass-band) signal with being input to received signal in the above-mentioned antenna 11; Above-mentioned by in the tuning signal, in order to keep the signal magnitude that is input in the A/D converter 14, the yield value that calculates is carried out AGC (Automatic GainControl) device 13 of multiplication process according to standard signal; Above-mentioned a certain size signal is carried out sampling (Sampling) handle, be converted to the A/D converter 14 of digital signal; Detect the mode detection apparatus 15 of the above-mentioned coded signal of turnover number transfer mode; Composite signal (ComplexSignal) real part (Real Part) of the above-mentioned coded signal of turnover number is reverted to the I/Q distributor 16 of composite signal; After removing protection interval unnecessary (Guard Interval),, time-domain signal is converted to the ofdm demodulator 8 of frequency domain by FFT (Fast FourierTransform); Utilize the input and output signal of above-mentioned ofdm demodulator 18, extract the signal Synchronization device 17 that is synchronized with information needed in signal time domain/frequency domain; At signal sending end, to the anti-interleaver 19 of frequency that is recovered to handle by staggered (Interleaving) subcarrier (Sub-carrier) signal location; The channel divider 1 that distributes control channel-FIC channel and data channel-MSC channel; Receive above-mentioned separated FIC channel, and therefrom separate the FIC decipher 21 of information needed in the deciphering of MSC channel; Receive above-mentioned MSC channel, and the anti-interleaver 22 of time that will in sender unit, be recovered to handle by the order of original frame by staggered 16 logical frame (Logical Frame); In the above-mentioned MSC channel of being managed by time reciprocal cross fault, correct the convolution decipher (Convolution decoder) 23 that transmits the random error (Random error) that takes place in the channel; By the above-mentioned data of having corrected, revert to the energy descrambler 24 of original data; Channel divider 2 25, the data channel that difference is transmitted is the audio/data signal that is applicable to the DAB server, still is applicable to the vision signal of DMB service; The audio/data signal that is applicable to above-mentioned separated DAB service is decrypted the audio/data decipher 29 of processing; Reception is applicable to the signal of above-mentioned DMB service, and will append the anti-interleaver of convolution (Convolution De-interleaver) 26 that staggered data are arranged by original order at signal sending end; At signal sending end, the RS decipher 27 that the coding of RS (Encoding) data are recovered to handle; The decryption of video device 30 that the vision signal that is applicable to DMB service is recovered to handle; The data that transmit by the FIC channel are decrypted the FIC data decryption device 28 of processing.

Above-mentioned DMB signal receiver can miniaturization, and development trend in the future is the form that combines with mobile phone, so the DMB signal receiving chip needs single-chip solution (one chip solution) form equally through the ASICization processing.

Therefore,, can in ASIC, reduce the door size, realize single-chip (one chip) change, have very important significance by reducing time reciprocal cross mistake.

Time deinterleaving method among the present invention is a kind of completely new approach that is referred to as multiple fragment (Multi-segment method), can reduce the memory size of being permitted in the time reciprocal cross mistake.

Carry out related description with reference to the accompanying drawings.

Fig. 4 is in the DMB signal receiver of the present invention, the key diagram of the wrong memory reducing method of time reciprocal cross.

At first, among the present invention, just be called fragment (segment) according to the memory unit that the i value changes size as Fig. 1 specification.

If in 16 frames, preserve 16 samples, the general memory that needs 16 * 16=256 size.

But in the memory of the present invention, only needing from size is till 15 fragment 9 is 8 fragment 14 to size, altogether 120 samples of 15 fragment sum totals.

And in the general memory using method, all samples all adopts identical mould pivot residual; But in the multiple-film phase method, each fragment adopts the mould pivot residual (modulo) of corresponding size, can remove obsolete in the memory (idle) part.

The firstth, read process, in this process, the value of first reading and saving in the wrong memory of time reciprocal cross, and export by anti-interleaver of time.

The secondth, ablation process is in this process, with the input content of anti-interleaver of write time in the wrong memory of the time reciprocal cross of reading the process identical address.

Like this, repeat reading and ablation process in the identical address memory, each fragment can reduce by a required memory.

For example, fragment 0 will be preserved 16 samples originally, read the process that afterwards writes earlier if adopt, and only preserved 15 and got final product.

Therefore, as shown in Figure 4, the size of fragment 0 is 15; If the input content in the anti-interleaver of 15 retention times of fragment just can realize reciprocal cross fault reason, memory that therefore need not be other.

By above-mentioned description, the related work personnel can carry out various change and modification fully in the scope that does not depart from this invention technological thought.

Therefore, the technical scope of this invention is not limited to the content on the specification, must determine its technical scope according to interest field.

Claims

1, the wrong memory reducing method of a kind of time reciprocal cross of DMB signal receiver, it is characterized in that: adopted in the DMB signal receiver required memory in the process of being carried out reciprocal cross fault reason by the data of staggered certain hour, the part that described memory only uses reality is carried out fragment and is handled, fragment adopts the mould pivot residual of corresponding size, with the fragment is that unit carries out time reciprocal cross fault reason, multiple being staggered in the process of reading, the value of elder generation's reading and saving in the wrong memory of time reciprocal cross, and export by anti-interleaver of time, in ablation process, with the wrong memory of the time reciprocal cross of reading the process identical address in the input content of anti-interleaver of write time.

2, the wrong memory reducing method of the time reciprocal cross of DMB signal receiver as claimed in claim 1 is characterized in that: above-mentioned memory possesses, and can to preserve size be 15 fragment 0 to size is 8 the fragment 14 positions storage space of 120 samples altogether.