CN100380957C - Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element - Google Patents

Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element Download PDF

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CN100380957C
CN100380957C CNB021498172A CN02149817A CN100380957C CN 100380957 C CN100380957 C CN 100380957C CN B021498172 A CNB021498172 A CN B021498172A CN 02149817 A CN02149817 A CN 02149817A CN 100380957 C CN100380957 C CN 100380957C
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ofdm
code element
sequence
unit
ofdm code
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CN1464748A (en
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丁海主
郭征元
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Samsung Electronics Co Ltd
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2626Arrangements specific to the transmitter only
    • H04L27/2627Modulators
    • H04L27/2634Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J11/00Orthogonal multiplex systems, e.g. using WALSH codes
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • H04L1/004Arrangements for detecting or preventing errors in the information received by using forward error control
    • H04L1/0041Arrangements at the transmitter end
    • H04L1/0042Encoding specially adapted to other signal generation operation, e.g. in order to reduce transmit distortions, jitter, or to improve signal shape
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2626Arrangements specific to the transmitter only
    • H04L27/2627Modulators
    • H04L27/264Pulse-shaped multi-carrier, i.e. not using rectangular window
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04JMULTIPLEX COMMUNICATION
    • H04J11/00Orthogonal multiplex systems, e.g. using WALSH codes
    • H04J2011/0003Combination with other multiplexing techniques
    • H04J2011/0006Combination with other multiplexing techniques with CDM/CDMA

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mathematical Physics (AREA)
  • Discrete Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Synchronisation In Digital Transmission Systems (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Radio Relay Systems (AREA)
  • Television Systems (AREA)
  • Noise Elimination (AREA)
  • Detection And Prevention Of Errors In Transmission (AREA)

Abstract

An OFDM transmitter inserting pseudo noise (PN) sequence into OFDM symbols after controlling the size of the pseudo noise sequence is provided. The OFDM transmitter includes: a FEC coding unit for coding input data to correct error of the reciever generating in correcting transport process; a IDFT unit converts coded data into OFDM code element; a GI (guide interval) inserting unit inserts a GI into an OFDM signal to repress interference between OFDM code elements; a PN generator unit generates 511 or 1023 length of PN sequence; a PN inserting unit inserts PN sequence into OFDM code element of GI, size of the PN sequence exceeds 255 code elements; a pulse shaping filter for filtering OFDM signal which has PN sequence instered; a RF upconversing unit for upconversing OFDM signal after filtering into radio frequency, and sending OFDM signal from channel.

Description

Adjust PN (pseudo noise) sequence and insert OFDM transmitter in the code element
Technical field
The present invention relates generally to a kind of OFDM (OFDM) transmitter and a kind of OFDM launching technique thereof, more specifically relate to OFDM transmitter and the OFDM launching technique thereof of before Domain Synchronous (TDS) sends an OFDM code element, in described OFDM code element, inserting pseudo noise (PN) sequence and protection interval (GI).
Background technology
Generally speaking, the broadcast system of high definition TV (HDTV) can roughly be divided into image encoding unit and image modulation unit.The image encoding unit will be the data of 15~18Mbps from the digital data compression of about 1Gbps of the image source of high definition input.Described image modulation unit sends the numerical data of tens Mbps to receiving terminal by the band limited channel of about 6~8MHz.HDTV uses terrestrial broadcast system, and this system uses the very high frequency(VHF)/hyperfrequency (VHF/UHF) that is allocated for the television broadcasting purpose.
In Europe, adopted as obtaining such as the television terrestrial broadcasting method of future generation of the transmission speed that improves every bandwidth with the advantage that prevents to disturb as OFDM (OFDM) method of one of Ditital modulation method.
It is the parallel data of unit that the code element stream that ofdm system is imported serial is converted to the piece, and parallel code element is multiplexed with different sub-carrier frequencies.Such ofdm system uses multicarrier, and is very different with the existing systems of using single carrier wave.Has orthogonal attributes between the described multicarrier.By the orthogonal attributes of multicarrier, the multiplying each other of two carrier waves with generation 0 value, this is to use one of necessary condition of multicarrier.Ofdm system is realized by two conversion: one is fast Fourier transform (FFT), another is inverse fast fourier transform (IFFT), and they are easily to obtain by the definition of orthogonality between subcarrier and fast Fourier transform (FFT).
The advantage of ofdm system is as follows:
According to the essence of TV method of terrestrially transmitting, the transmission quality of the data of TV ground transmission system depends critically upon reflected wave and in same channel or the interference between adjacent channel.Therefore the designing requirement for transmission system is very complicated.On the contrary, ofdm system is very healthy and strong for the multipath attribute.In other words, because ofdm system uses various carrier waves, therefore can prolong the code element transmission time.Therefore, transfer of data becomes for the interference signal anti-interference owing to multipath, even also like this for the echo-signal that the long period takes place.And ofdm system is also very healthy and strong to existing signal type, so it is subjected in the influence of the interference of same interchannel less.Because above-mentioned ofdm system like this, can realize a single-frequency network (SFN), by it, a broadcasting station can be carried out the broadcasting in the whole nation with a single frequency.During the transmission, the interference in same channel may be very strong, but can overcome in ofdm system, and ofdm system is healthy and strong for such data transmission environments.Owing to used the single-frequency network, can more effectively use limited frequency resource.
Ofdm signal comprises multicarrier, and each has little bandwidth.Because it is square that the shape of whole frequency spectrum comes down to, frequency efficiency is better than the single carrier wave of use.Another advantage of ofdm system is that the waveform of ofdm signal is identical with white Gauss noise.That is, because ofdm signal has and the similar waveform of white Gauss noise, therefore with such as other the broadcasting service that changes phase place (PAL), "systemme electronique couleur avec memoire" etc. with line compare, it has less interference.Owing in ofdm system, can be possible, have therefore enabled the individual-layer data transmission for the modulation of each carrier wave.
Generally, the OFDM transmitter Domain Synchronous ground that utilizes Domain Synchronous to send ofdm signal will provide the ofdm signal that produces with respect to frequency axis for the intended service of predetermined frequency band to be converted to data with respect to time shaft.Before the transmission OFDM signal, the OFDM transmitter inserted a protection interval GI so that suppress inter-signal interference before the ofdm signal that forms along time shaft, and inserted synchronizing information before the GI at interval in protection.
Fig. 1 is the figure that the structure of an ofdm signal frame is shown, and it is formed by the OFDM transmitter of a traditional TDS type during transfer of data.
The frame of ofdm signal is constructed such that GI and PN sequence are inserted in the OFDM code element that comprises the data that will send.In other words, the OFDM code element comprises the data that will send to the OFDM receiver.GI is certain zone of distributing, is used to suppress inter symbol interference.The PN sequence is the synchronizing information for each OFDM code element.The PN sequence is used to synchronously and channel estimating at the OFDM receiver.
The OFDM code element that is included in the frame of the ofdm signal that is sent by traditional OFDM transmitter is set to carry out contrary discrete Fourier transform (DFT) by a plurality of subcarriers with 3,780 points.And after the IDFT of OFDM, GI is inserted in the OFDM code element with 1/6,1/9,1/20 or 1/30 size corresponding to 3,780 points of OFDM code element.The PN sequence is inserted in the OFDM code element of inserting GI with the size corresponding to 255 code elements.
Problem is, compares with the size of the OFDM code element that is included in 3,780 points in a plurality of subcarriers, and 255 code elements of the size of PN sequence are quite little.Therefore, the OFDM receiver that receives ofdm signal with such frame be difficult to utilize the PN sequence that is included in the ofdm signal that is received carry out for the ofdm signal that is received synchronously and channel estimating.As a result, the frequent ofdm signal that received of reduction inaccurately of OFDM receiver.
Summary of the invention
Therefore, an object of the present invention is to provide a kind of OFDM (OFDM) transmitter, it can adjust the size that is inserted into the PN sequence in the OFDM code element before sending ofdm signal, so that the PN sequence in the OFDM code element that the OFDM receiver can receive based on being inserted into and carrying out more accurately synchronously and channel estimating, the present invention also provides the sending method of a kind of OFDM of correspondence.
To achieve these goals, at an OFDM transmitter in---it inserted protection (GI) and pseudo noise (PN) sequence at interval in the described OFDM code element that will send before sending an OFDM code element---, comprise according to OFDM transmitter of the present invention: a FEC coding unit, be used to the data of input of encoding, so that correct the mistake that takes place at receiver during the transmission; One contrary discrete Fourier transform (DFT) (IDFT) unit, being used for described coded data converting is the OFDM code element; One protection is inserted the unit at interval, is used for inserting GI in the OFDM code element after the IDFT of OFDM code element, so that suppress inter symbol interference; One PN generator unit is used to produce 511 or 1023 length of PN sequence; One PN inserts the unit, is used for inserting the PN sequence in the OFDM code element of inserting GI, and the size of described PN sequence surpasses 255 code elements; One pulse shaping filtering unit is used for carrying out shaping pulse filtering for the OFDM code element that is inserted into the PN sequence; With a RF up-conversion unit, be used for ofdm signal is transformed to radio frequency to send ofdm signal by a channel.
Preferably, described GI inserts the unit and insert GI in described OFDM code element after the IDFT of described OFDM code element, its big small mode is corresponding to 1/6,1/9,1/20 or 1/30 of the OFDM code element, and perhaps its big small mode is corresponding to 1/20,1/30,1/36 or 1/40 of the OFDM code element.
Preferably, PN insertion unit insertion size in the OFDM code element of inserting GI is 500 to 520 or 1,000 to 1,040 PN sequence.And it is the PN sequence of 511 code elements or 1,023 code element that PN inserts unit insertion size in the OFDM code element of inserting GI.
Preferably, comprise also that according to OFDM transmitter of the present invention preamble/postamble inserts the unit, be used for inserting a preamble and a postamble to form a new PN sequence in the PN sequence.
And, at an OFDM transmitter in---it inserted protection (GI) and pseudo noise (PN) sequence at interval in the described OFDM code element that will send before sending an OFDM code element---, a kind of OFDM launching technique comprises step: the data of coding input, so that be corrected in the mistake that takes place at receiver during the transfer of data; With the contrary discrete Fourier transform (DFT) of described coded data is the OFDM code element; Insert GI in the OFDM code element, so that suppress inter symbol interference; Produce 511 or 1 023 length of PN sequence by a PN generator unit; Insert the PN sequence in the OFDM code element of inserting GI, the size of described PN sequence surpasses 255 code elements; Carry out shaping pulse filtering for the OFDM code element that is inserted into the PN sequence; With after shaping pulse filtering OFDM code element with ofdm signal RF up conversion.
Preferably, described GI inserts the unit and insert GI in described OFDM code element after the IDFT of described OFDM code element, its big small mode is corresponding to 1/6,1/9,1/20 or 1/30 of the OFDM code element, and perhaps its big small mode is corresponding to 1/20,1/30,1/36 or 1/40 of the OFDM code element.
Preferably, PN insertion unit insertion size in the OFDM code element of inserting GI is 500 to 520 or 1,000 to 1,040 PN sequence.And it is the PN sequence of 511 code elements or 1,023 code element that PN inserts unit insertion size in the OFDM code element of inserting GI.
Preferably, described OFDM transmission method also comprises step: insert a preamble and a postamble to form a new PN sequence in described PN sequence.
Because before the described OFDM code element of transmission, described size is that the PN sequence of 511 code elements or 1,023 code element is inserted in the described OFDM code element, is used for the synchronous and channel estimating of receiving terminal, therefore, the OFDM receiver can be carried out the synchronous and channel estimating of the OFDM code element that is received more accurately.As a result, the OFDM receiver can reduce the data that received more accurately.
And, because receiver can be 511 code elements or 1 from the size being inserted into described OFDM code element, carry out the synchronous and channel estimating of the OFDM code element that is received in the PN sequence of 023 code element more accurately, therefore can reduce to insert the size of the GI that suppresses inter symbol interference.As a result, can improve the transfer rate of OFDM code element.
Description of drawings
By reference description of drawings the preferred embodiments of the present invention, above-mentioned purpose of the present invention and characteristics will become apparent, wherein:
Fig. 1 is the figure that the structure of ofdm signal frame is shown, and described ofdm signal frame is formed by a traditional TDS type OFDM transmitter between the ofdm signal transmission period;
Fig. 2 is the block diagram according to the OFDM transmitter of the preferred embodiments of the present invention;
Fig. 3 (a) is a PN generator that comprises 9 linear feedback shift registers;
Fig. 3 (b) is a PN generator that comprises 10 linear feedback shift registers;
Fig. 4 is the figure that the structure of the ofdm signal frame that is formed by Fig. 2 is shown;
Fig. 5 illustrates to be used to use the flow chart that sends the method for ofdm signal according to OFDM transmitter of the present invention.
Embodiment
Below, illustrate in greater detail the preferred embodiments of the present invention with reference to accompanying drawing.
As shown in Figure 2; according to one embodiment of the present of invention; a kind of OFDM transmitter comprises forward error correction (FEC) unit 100, contrary discrete Fourier transform (DFT) (IDFT) unit 200, and unit 300, PN generator 400, the insertion of pseudo noise (PN) sequence unit 500, pulse shaping unit 600 and radio frequency (RF) up-conversion unit 700 are inserted in protection (GI) at interval.
FEC unit 100 coding OFDM code elements are used to correct the mistake that takes place during the transmission.IDFT unit 200 is for carrying out IDFT in FEC coding unit 100 coded OFDM code elements.
When after the IDFT of IDFT unit 200, GI inserts unit 300 and insert a protection (GI) at interval in the OFDM code element, to suppress inter-signal interference.At this moment, the big small mode of GI corresponding in the IDFT unit 200 by 1/6,1/9,1/12,1/20 or 1/30 of the OFDM code element of contrary discrete Fourier transform (DFT).
As a kind of selection, GI inserts unit 300 can insert GI with the big small mode corresponding to 1/12,1/20,1/30,1/36 or 1/40.Therefore, can improve the effective ratio of transmission of the OFDM code element in the ofdm signal frame.
PN generator 400 generation length are 511 or 1023 PN sequence.
Then, PN inserts unit 500 and insert the PN sequence in is inserted the OFDM code element of GI with predetermined big small mode.At this moment, PN inserts unit 400 and insert the PN sequence that size surpasses 255 code elements in the OFDM code element of inserting GI.Preferably, PN inserts unit 400 inserts 511 code elements or 1,023 code element in the OFDM code element of inserting GI PN sequence.
The PN sequence of 511 code elements or 1,023 code element as mentioned above be inserted in the OFDM code element after, pulse shaping unit 500 comes shaping pulse filtering OFDM code element according to the predetermined roll-off factor of OFDM code element.
The OFDM code element of RF up-conversion unit 700 high frequency conversion shaping pulses is so that send them by antenna 800 and transmission channel to the OFDM receiver.
Since be used for receive a side synchronously and 511 code elements of channel estimating or the PN sequence of 1,023 code element be included in the OFDM code element that will send, so the OFDM receiver can be carried out the synchronous and channel estimating for the ofdm signal that is received more accurately.As a result, the OFDM receiver can reduce the ofdm signal that is received more accurately.
And, because inserting size in the OFDM code element is 511 code elements or 1, the PN sequence of 023 code element makes that receiving one can reach the synchronous and channel estimating of carrying out more accurately for the ofdm signal that is received, and therefore can reduce to insert the size of the GI that suppresses inter symbol interference.As a result, improved the transfer rate of OFDM code element.
Fig. 3 (a) and (b) be to be respectively to be used to produce the PN generator that length is 511 and 1023 PN sequence according to the preferred embodiments of the present invention.
Shown in Fig. 3 (a), the PN generator comprises an XOR and contains linear feedback shift register (LFSR) circuit of 9 shift register D, so it constitutes one 511 PN sequencer of the present invention.
Shown in Fig. 3 (b), the PN generator comprises an XOR and contains the LFSR of 10 shift register D, therefore constituted one 1023 PN sequencer of the present invention.
Fig. 4 is the figure of an example that the structure of the ofdm signal frame that is formed by Fig. 2 is shown.
As shown in Figure 4, the frame of ofdm signal comprises an OFDM code element that comprises the data that will send, and a GI and a PN sequence of being inserted into the OFDM code element.
According to the preferred embodiments of the present invention, a plurality of subcarriers of being order by N by the OFDM code element of OFDM transmitter transmission carry out contrary discrete Fourier transform (DFT).Described N point comprises 3,780 points, 2,048 points, 4,096 and 8,192 points, and 2,048 points, and 4,096 points, 8,192 the pattern of a plurality of subcarriers are respectively 2K pattern, 4K pattern and 8K pattern.
GI with corresponding to respect to the OFDM code element really the size of sizing be inserted in the OFDM code element of a plurality of subcarriers that N orders.The described size of determining with respect to the OFDM code element is 1/6,1/9,1/12,1/20 or 1/30 of an OFDM code element, perhaps also can be one of 1/12,1/20,1/30,1,/36 1/40 of OFDM code element.
Fig. 5 is a flow chart, shows according to the preferred embodiments of the present invention and sends the method for ofdm signal by utilizing the OFDM transmitter.
At first, the OFDM code element that FEC coding unit 100 codings will send is to be corrected in the mistake (step S100) that takes place during the transfer of data.After by FEC coding unit 100 codings, IDFT (step S120) is carried out for the OFDM code element that is encoded in IDFT unit 200.
After the IDFT of OFDM code element, GI inserts unit 300 and insert GI in the OFDM code element, so that suppress inter symbol interference (step S140).At this moment, GI inserts unit 300 and inserts GI, and its size is corresponding to a definite pattern, promptly 1/6 of the OFDM code element, 1/9,1/12,1/20 or 1/30, or the OFDM code element 1/12,1/20,1/30,1/36 or 1/40.Therefore, can improve the transfer rate of the OFDM code element of ofdm signal frame.
PN generator 400 generation length are 511 or 1023 PN sequence (step S160).
PN inserts unit 500 and insert the PN sequence in the OFDM code element of inserting GI, and its size is for surpassing 255 code elements (step S180).Preferably, PN inserts unit 500 inserts 511 code elements or 1,023 code element in the OFDM code element of inserting GI PN sequence.
Pulse shaping unit 600 comes shaping pulse filtering to be inserted into the OFDM code element (step S200) of the PN sequence of 511 code elements or 1,023 code element according to predetermined roll-off factor.
The OFDM code element of RF up-conversion unit 700 high frequency conversion shaping pulse filtering is to come to send OFDM code element (step S220) to the OFDM receiver via transmission channel.
According to the present invention, because inserted size before the transmission OFDM code element in the OFDM code element is 511 code elements or 1, the PN sequence of 023 code element is to be used for the synchronous and channel estimating at receiving terminal, therefore can reduce to insert the size of the GI that suppresses inter symbol interference, as a result, can improve the transfer rate of OFDM code element.
Though the preferred embodiments of the present invention have been described, those skilled in the art will appreciate that to the invention is not restricted to described preferred embodiment, can make various improvement and change in the spirit and scope of the present invention of Xian Dinging in the appended claims.

Claims (11)

1. one kind is inserted the OFDM transmitter of protecting interval (GI) and pseudo noise (PN) sequence in an OFDM code element, and described OFDM transmitter comprises:
One FEC coding unit is used to the data of input of encoding, so that correct the mistake that takes place at receiver during the transmission;
One contrary discrete Fourier transform (DFT) (IDFT) unit, being used for described coded data converting is the OFDM code element;
One protection is inserted the unit at interval, is used for inserting GI in the OFDM code element after the IDFT of OFDM code element, so that suppress inter symbol interference;
One PN generator unit is used to produce 511 or 1023 length of PN sequence;
One PN inserts the unit, is used for inserting the PN sequence that is produced by the PN generator unit in the OFDM code element of inserting GI, and the size of described PN sequence surpasses 255 code elements;
One pulse shaping unit is used for carrying out shaping pulse filtering for the OFDM code element that is inserted into the PN sequence; With
A RF up-conversion unit is used for ofdm signal is transformed to radio frequency to send ofdm signal by a channel.
2. according to the OFDM transmitter of claim 1, wherein said GI inserts the unit and insert GI in described OFDM code element after the IDFT of described OFDM code element, and its big small mode is corresponding to 1/6,1/9,1/20 or 1/30 of the OFDM code element.
3. according to the OFDM transmitter of claim 1, wherein said PN generator is the linear feedback shift register (LFSR) that comprises 9 or 10 shift registers.
4. according to the OFDM transmitter of claim 1, wherein it comprises that also a preamble/postamble inserts the unit, is used for inserting a preamble and a postamble to form a new PN sequence in the PN sequence.
5. according to the OFDM transmitter of claim 4, wherein when the PN generator is a kind of linear feedback shift register that comprises 9 shift register D, the length of described new PN sequence is 511 code elements.
6. according to the OFDM transmitter of claim 4, wherein when described PN generator is a kind of linear feedback shift register that comprises 10 shift register D, the length of described new PN sequence is 1023 code elements.
7. the protection OFDM launching technique of an OFDM transmitter of (GI) and pseudo noise (PN) sequence is at interval inserted in a utilization in an OFDM code element, and described OFDM launching technique comprises step:
The data of coding input are so that be corrected in the mistake that takes place at receiver during the transfer of data;
With the contrary discrete Fourier transform (DFT) of described coded data is the OFDM code element;
Insert GI in the OFDM code element, so that suppress inter symbol interference;
Produce 511 or 1023 length of PN sequence by a PN generator unit;
Insert the PN sequence that is produced by the PN generator unit in the OFDM code element of inserting GI, the size of described PN sequence surpasses 255 code elements;
Carry out shaping pulse filtering for the OFDM code element that is inserted into the PN sequence; With
After shaping pulse filtering OFDM code element with ofdm signal RF up conversion.
8. according to the OFDM launching technique of claim 7, wherein the big small mode of the described GI that inserts in described OFDM code element after the IDFT of described OFDM code element is corresponding to 1/6,1/9,1/20 or 1/30 of described OFDM code element.
9. according to the OFDM launching technique of claim 7, wherein also comprise step: in described PN sequence, insert a preamble and a postamble to form a new PN sequence.
10. according to the OFDM launching technique of claim 9, wherein when the PN generator is a kind of linear feedback shift register that comprises 9 shift register D, the length of described new PN sequence is 511 code elements.
11. according to the OFDM launching technique of claim 9, wherein when described PN generator is a kind of linear feedback shift register that comprises 10 shift register D, the length of described new PN sequence is 1023 code elements.
CNB021498172A 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element Expired - Fee Related CN100380957C (en)

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KR33601/02 2002-06-17
KR1020020033601A KR20030096624A (en) 2002-06-17 2002-06-17 OFDM transmitter capable of adjusting size of PN and inserting adjusted PN into OFDM symbol
KR33601/2002 2002-06-17

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CNA2008100741060A Division CN101257476A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741022A Division CN101257474A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100058007A Division CN101242386A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006100922599A Division CN1870482A (en) 2002-06-17 2002-11-06 OFDM transmitter inserting pseudo noise sequence into OFDM symbols after controlling pseudo noise queue
CNA200810074108XA Division CN101257478A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741018A Division CN101257473A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741107A Division CN101257479A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741075A Division CN101257477A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006100922601A Division CN1870483A (en) 2002-06-17 2002-11-06 OFDM transmitter inserting pseudo noise sequence into OFDM symbols after controlling pseudo noise queue
CNA2008100741037A Division CN101257475A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element

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CN100380957C true CN100380957C (en) 2008-04-09

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CNA2008100741075A Pending CN101257477A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006101629590A Pending CN101141432A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006101629603A Pending CN101141433A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741022A Pending CN101257474A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741107A Pending CN101257479A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741018A Pending CN101257473A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006100922601A Pending CN1870483A (en) 2002-06-17 2002-11-06 OFDM transmitter inserting pseudo noise sequence into OFDM symbols after controlling pseudo noise queue
CNA2008100741037A Pending CN101257475A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA200810074108XA Pending CN101257478A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNB021498172A Expired - Fee Related CN100380957C (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006100922599A Pending CN1870482A (en) 2002-06-17 2002-11-06 OFDM transmitter inserting pseudo noise sequence into OFDM symbols after controlling pseudo noise queue
CNA2008100058007A Pending CN101242386A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element

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CNA2008100741060A Pending CN101257476A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741075A Pending CN101257477A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006101629590A Pending CN101141432A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006101629603A Pending CN101141433A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741022A Pending CN101257474A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741107A Pending CN101257479A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2008100741018A Pending CN101257473A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
CNA2006100922601A Pending CN1870483A (en) 2002-06-17 2002-11-06 OFDM transmitter inserting pseudo noise sequence into OFDM symbols after controlling pseudo noise queue
CNA2008100741037A Pending CN101257475A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element
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CNA2008100058007A Pending CN101242386A (en) 2002-06-17 2002-11-06 Orthogonal frequency division multiplexing transmitter with modified pseudo-random noise sequence and inserted code element

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KR100683865B1 (en) * 2004-03-03 2007-02-15 이창수 Polyphase Filter Orthogonal Frequency Division Multiplexing System : OFDM System
CN115174328B (en) * 2021-04-02 2023-12-08 华为技术有限公司 Data processing method and communication equipment

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CN101242386A (en) 2008-08-13
CN1870483A (en) 2006-11-29
CN101141433A (en) 2008-03-12
CN1870482A (en) 2006-11-29
CN101257479A (en) 2008-09-03
CN101141432A (en) 2008-03-12
CN1464748A (en) 2003-12-31
CN101257474A (en) 2008-09-03
CN101257475A (en) 2008-09-03
CN101257476A (en) 2008-09-03
CN101257478A (en) 2008-09-03
CN101257477A (en) 2008-09-03
CN101257473A (en) 2008-09-03
KR20030096624A (en) 2003-12-31

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