CN1643838A - Sychronization data detection unit and method - Google Patents
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- H04W56/0055—Synchronisation arrangements determining timing error of reception due to propagation delay
- H04W56/0065—Synchronisation arrangements determining timing error of reception due to propagation delay using measurement of signal travel time
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- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
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- H04L7/00—Arrangements for synchronising receiver with transmitter
- H04L7/02—Speed or phase control by the received code signals, the signals containing no special synchronisation information
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Abstract
A synchronization data detecting unit is provided in a communication system for detecting predetermined synchronization data. The synchronization data are sent in a transmission frame in a communication signal of the communication system. The synchronization data include a sequence of identical binary symbols which are transmitted after scrambling. The synchronization detection unit comprises a descrambler for descrambling the received communication and for producing an output data sequence having multi-level signal values. The multi-level signal values of the descrambler output are smoothed in a filter unit. The smoothed signal is compared with a predetermined threshold value. If the smoothed signal exceeds the predefined threshold value, a detection of said synchronized data is indicated.
Description
Technical field
Present invention is directed to a kind of Sychronization data detection unit and method that detects predetermined synchrodata, and particularly relevant for a kind of receiver and method of reseptance in a WLAN (WLAN, Wireless localarea network) communication system.
Background technology
Such as being in the communication system of WLAN (WLAN) system, it is important allowing receiver be synchronized with transmitter, and this information that makes can successfully exchange between this transmitter and this receiver.WLAN system is a kind of rubber-like data communication system, can be embodied as the extension or another kind of selection of wired local area network.Wlan system utilizes radio frequency or infrared technology and transmits and receive data to reduce to the demand of connecting line minimum by air.Therefore, this wlan system has data link and user's mobility concurrently.
Most wlan system system uses spread spectrum, and this spread spectrum is to be used in the wide band radio-frequency technology that develops in reliable and the fail safe communication system.This spread spectrum system is designed to obtain the balance point of frequency range service efficiency between reliability, conformability and fail safe.Two kinds of spread spectrum wireless systems systems that often use: frequency hopping (frequency hoping) and direct sequence (DirectSequence) system.
In the direct sequence spread spectrum skill system, utilize character code with upper frequency and higher information bit rate and character (symbol) that each data bit is encoded and finish spread spectrum." spread spectrum " of gained back signal system is distributed on the big frequency range, and this will cause quite low power spectrum density, makes other communication system more can not be subjected to transmitting the interference of the device of this Direct Sequence Spread Spectrum Signal.Direct sequence spread spectrum skill is used this transmitter and receiver is all known emulation (pseudo) random noise character code with these data of spread spectrum.This character code comprises a series of " small-pulse effect (chip) " that is multiplied by (or carrying out " mutual exclusion or " logical operation) by this information bit waiting for transmission.Many wireless networks conform are used 802.11 standards of the IEEE (Institute of Electricaland Electronics Engineers, Institute of Electrical and Electronics Engineers) of known Bark (Barker) character code and are encoded and these data of spread spectrum.This barker code word consists comprises a string 11 predetermined small-pulse effects.In the shared time cycle, is transmission one whole string barker code word consists at the character that comprises information.
For allowing higher data transmission rate, this IEEE802.11 standard extends to IEEE802.11b.Except this barker chip of 11, this IEEE802.11b standard is used 8 mutual-complementing code shift keies (Complementary Code Keying of high data transmission rate; Be called for short CCK) algorithm.
Use the more modulation technique of high-order, comprise that (Quadrature PhaseShift Keying, QPSK), this data transmission rate can be improved and becomes to be higher than this character rate for orthogonal PSK modulation.According to this kind modulation technique, everybody is represented by the higher number of possible phase place.Thereby this transmitter produces two signals, and first signal is called " same-phase (I) signal or " I channel ", and second signal is called " quadrature phase " (Q) signal or " Q channel " of the sinusoidal carrier of 90 degree phase shifts under same frequency.
Use this IEEE802.11 standard application of the WLAN of direct sequence spread spectrum skill to train package (training preamble) with of the transmission of training receiver to transmitter.Each transmitting data information comprises an initial training package of the data field that continuing.This package system comprises a synchronous field, can carry out necessary simultaneous operation to confirm this receiver.For this package length, defined two kinds of selections, that is a long package and a short package.All systems that accord with the 802.11b standard must support this long package.This weak point package is the efficient that selectivity is provided in this standard the network throughput when improving the special data when transfer ratio such as sound or image etc.The synchronization field of long package comprises that 128 is 1 position, and the synchronization field of short package comprises that 56 is 0 position.
Receiver detect this synchronizing symbol and with the internal frequency of this receiver in alignment with this symbol in this synchronization field to set up a fixing reference time frame (time frame) with continue those fields in this transmission frame-form behind this package of decipher.Comprise that this package system of this synchronization field is transmitted in the beginning (data packet) of each information.
The purpose of preamble detection unit is the input signal of monitoring this package constantly, and points out to detect whether this package.Determine continuous Bark symbol or the intersymbol border of CCK, and the sequential that transmits of this symbol is the treatment schedule that is synchronized with this receiver forward.According to the timing skew between the treatment schedule of this preamble detection and the symbol time of advent and subsequent module, this input signal is synchronized with the treatment schedule of this receiver.
Please refer to Fig. 1 now, it is illustrated in the detection that detects a package in the communication signal and handles.After receiving the step 100 of communication signal and this communication signal that is received is further being handled, particularly before decoding step 102, carry out preamble detection step 101.
The framework system of tradition preamble detector 200 is illustrated in Fig. 2.The communication signal 201 that comprises this reception of same-phase and quadrature phase composition is input to this preamble detector 200.In this preamble detector 200, the communication signal 201 of this reception at first inputs to despreader (despreader) 204, but special case is Bark matched filter (BMF, Barker matched fiker).Communication signal through separating spread spectrum inputs to demodulator, and (demodulator, DEM) 205 to carry out rectification to the communication signal through separating spread spectrum.Signal behind the rectification comprises that determining sequence that is to say position " firmly " in proper order that receives, and each data value of the signal behind the rectification is one of two possible binary values.Bit stream behind the monitoring rectification is to detect this predefined packet data.Generally speaking, use a correlator (correlator) to detect this package.This correlator is essentially a matched filter of this preamble sequence.When this package existed, this correlator produced the output with big numerical value.When the numerical value of this correlation surpasses a predefined threshold value, can declare formally to detect package.
After detecting package, through this communication signal of rectification be input to one (numeral) decoder (descrambler, DDS).One example of the decoder 300 that known technology is used is illustrated among Fig. 3.According to predefined decoding principle, input signal 301a is input to the delay square 304 and 305 of representative with several units of time delay.This delayed signal is fed and utilizes multiplier or XOR gate 306 and merges.This output signal is fed to this input signal 301b and utilizes multiplier or XOR gate 303 and merging, to produce the output signal 302 through decoding.
Sychronization data detection unit still has several problems.One of problem is exactly, and noise may reduce this signal quality, makes this lock unit, particularly this preamble detector, can't correctly recognize package, even in this communication signal that has package to be present in to be received.When not having real package and exist, noise also may produce an output signal above this threshold value.
Summary of the invention
The invention provides a kind ofly through improved synchronous detection unit and method, it is difficult for producing mistake detecting on the predefined synchrodata.
According to an aspect of the present invention, in a communication system, provide a kind of Sychronization data detection unit, in order to detect the predetermined synchrodata in the transmission frame in the communication signal.This synchrodata comprises an identical binary symbol sequence, and it was being sent encoder to be transmitted later on.This Sychronization data detection unit comprises: a decoder, the dateout string that this communication signal that is received to decode and generation have the multilevel signal value.This multilevel signal value is input to the output of a filter with level and smooth this decoder.Signal after being somebody's turn to do smoothly is input to a threshold device.This threshold device is with output and predetermined threshold comparison behind this filter level and smooth.If this output of this filter surpasses this predetermined threshold, then this threshold device indication detects this synchrodata.
In another embodiment, this filter is a comb filter.
In another embodiment, this comb filter comprises the predetermined number of identical decay part, the input signal that receives with continuous delay, and in order to accumulate this input signal and the collecting apparatus of the output signal of this decay part respectively.
In another embodiment, this comb filter comprises in addition by this numeral (n) of accumulating signal and divides the modular station of this accumulation results.
In another embodiment, respectively this decay part is made of the predetermined number of the buffer that is connected in series.
In another embodiment, the predetermined number of this buffer is greater than 5.
In another embodiment, this comb filter comprises at least nine decay parts.
In another embodiment, this threshold device surpasses the detection that this predetermined threshold (Th) back shows this synchronizing signal in the predetermined number of determining continuous accumulation results.
In another embodiment, the predetermined number of this continuous accumulation results is 5 to 20 a numeral.
In another embodiment, the predetermined number of this continuous accumulation results is greater than 10.
In another embodiment, this threshold device provides at least two threshold value (Th
1, Th
2) so that distinguish and detect the synchronizing signal of different length in this communication signal.
In another embodiment, this threshold device comprises in order to detect the first threshold value (Th of longer synchronizing signal
1) and detect the second threshold value (Th of the synchronizing signal of weak point
2).
In another embodiment, this first and second threshold value (Th
1, Th
2) have same absolute value but different symbols is arranged.
In another embodiment, the direct sequence spread spectrum frequency spectrum transport architecture of utilizing this communication system transmits this communication signal and this synchronous signal detection unit and further comprises and separate the spread spectrum unit to what the communication signal that receives was separated spread spectrum, and this is separated the demodulating unit of the communication signal demodulation of spread spectrum.
In another embodiment, this communication system is WLAN (WLAN) system.
In another embodiment, the WLAN receiver comprises the synchronous signal detection unit according to above-mentioned any embodiment.
According to another aspect of the present invention, provide a kind of method that is used for receiving isochronous data in the communication system.Predetermined synchrodata is included in the interior transmission frame of a communication signal.This synchrodata comprises the identical binary symbol sequence that transmits again behind the coding.This communication signal that is received is decoded to produce a multilevel signal value sequence.Level and smooth this multistage output signal value; And a signal and a predetermined threshold after will being somebody's turn to do smoothly compare.If the signal after being somebody's turn to do smoothly surpasses this predetermined threshold, then representative detects this synchrodata.
In one embodiment, this signal value of this level and smooth step decoded signal that will receive averages.
In another embodiment, this average step comprises:
The input signal that repeatedly postpones this reception continuously;
Accumulation is this inhibit signal part and this input signal respectively; And
Export this accumulating signal.
In another embodiment, divide this accumulating signal by this numeral of accumulating signal part and with this output signal standardization.
In another embodiment, this first and this second threshold value (Th
1, Th
2) have identical absolute value but different symbols is arranged.
In another embodiment, this communication signal utilizes the transmission of direct sequence spread spectrum frequency spectrum transport architecture and this communication signal to separate spread spectrum and demodulation earlier before decoding.
In another embodiment, be used for comprising step according to the detection synchronizing signal of said method in the method that communication system receives communication signal.
Description of drawings
One flow chart of Fig. 1 illustration preamble detection flow process;
Fig. 2 illustration detects the calcspar of a preamble detector of the package in a communication signal;
Fig. 3 illustration is contained in the calcspar of the framework of the decoder in the preamble detector as shown in Figure 2;
The calcspar of Fig. 4 exemplary synchronization Data Detection unit;
Fig. 5 illustration is contained in the calcspar of the framework of a medium-soft (half-soft) decoder module in this framework as shown in Figure 4;
The calcspar of the more specific embodiment of this decoder module that Fig. 6 illustration Fig. 5 is shown;
The calcspar of the framework of the filter module in shown this framework of Fig. 7 illustration Fig. 4;
The calcspar of the another kind of framework of the filter module in shown this framework of Fig. 8 illustration Fig. 6;
One flow chart of Fig. 9 illustration preamble detection handling process;
Figure 10 is illustrated in the flow chart that the threshold value that detects predetermined synchrodata in the communication signal compares flow process; And
Figure 11 is illustrated in the flow chart that the more detailed threshold value that detects two kinds of different packages in the communication signal compares flow process.
Embodiment
Referring now to accompanying drawing embodiments of the invention are described.
Please refer to accompanying drawing now, particularly with reference to figure 4, a kind of Sychronization data detection unit of Fig. 4 illustration is used to detect synchrodata, particularly predefined package.Framework comprises a synchrodata detection module 400 and a synchronous module 403 as shown in Figure 4.This synchrodata detection module 400 detects a package, and the timing skew between the treatment progress (processing schedule) of a symbol time of advent and this subsequent module also is provided.This symbol synchronizer 403 utilize this timing skew information with synchronization of data streams in this treatment progress.
This synchrodata detection module 400 comprises following modules: a Bark matched filter (BMF, Barker matched filter) module 404, (soft descrambler, SDS) module 406 for difference BPSK demodulator (DEM) module 405 and one soft decoder.Those modules that is to say that BMF, DEM and SDS form discordant (non-coherent) receiver.Even this synchrodata detection module 400 comprises a comb filter, and (comb filter, COF) module 407 is with the output of level and smooth this decoder.For assessing these data after level and smooth to detect this predefined packet data, this synchrodata detection module 400 comprises a thresholding controller 408.The details of above-mentioned module will be described below.
This Bark matched filter module 404 receives and inputs to this communication signal 401 of this synchrodata detection module 400, and calculates the correlation between the sampling value of this barker sequence and this input signal.This barker code word consists comprises 11 small-pulse effects, and the order of these 11 small-pulse effects is that " 01001000111 " or "+1 ,-1 ,+1 ,+1 ,-1 ,+1 ,+1 ,+1 ,-1 ,-1 ,-1 " (NRZ), wherein leftmost small-pulse effect is exported at first for non-return-to-zero, non-return-to-zero.Complete barker code word consists is received in by the symbol that contains information in occupied period.Therefore, if this symbol rate is the 1M baud, the basic small-pulse effect rate of 11 small-pulse effects of this of this barker sequence is 11MHz.By using the small-pulse effect rate signal of this 11MHz, the occupied frequency spectrum of this transmission signals can become 11 times big.In one embodiment, because input sampling rate is the relation of 22Msps, this barker sequence is extended into 22 samplings from 11 samplings.This can reach by being incorporated between the primitive element of this barker sequence 0.
The input sampling of I channel and Q channel is relevant to this barker sequence respectively.Be each compound input sampling calculated complex coherent sampling.This can realize by " slip-window (sliding-window) " algorithm of techniques well known.
The communication signal of separating spread spectrum (despread) inputs to this demodulator module 405.In specific embodiments, this demodulator module 405 is differential BPSK demodulators.
Please refer to Fig. 5 and Fig. 6 now, its illustration the particular embodiment of decoder module 406.This decoder module 406 can be embodied as the soft decoder that can export many-valued sampling.With respect to digital solution modulation device, in soft decoder inside, many-valued input signal is not subjected to the processing of " hard (hard) " binarization, but this output valve through decoding is to arrange with the binary value of this expectation.
Among described herein other embodiment, " medium-soft (half-soft) " decoder is used to the signal through rectification is decoded.The example of the framework of " medium-soft " decoder module 500 is shown among Fig. 5 and Fig. 6.Half-soft descrambler and soft decoder different are in, this input signal 501a of " postponing partly " 504 to 506 that inputs to this decoder inside by binarization, and other of this input signal 501b partly still is maintained in multi-valued signal.In the decoder module 500 of Fig. 5, this input signal 501a that is received is input to binarization part 503 to convert many-valued input sampling value to binary value.
This decoder module 500 is to dispose according to predefined generator polynomial, and this multinomial is such as being 1+x
a+ x
b, x wherein
aWith x
bRepresent predefined time delay.Delayed signal utilizes multiplier or XOR gate and feeds back and be injected towards this input signal to produce the output through decoding.As shown in Figure 6, this Delay Element 504 and 505 comprises a plurality of 1 buffer 601 to 606, and each buffer is represented the time delay of a unit.Sequence of soft-symbols of arranging of this half-soft descrambler output along this expectation binary value.
The advantage of this half-soft descrambler configuration of Fig. 5 and Fig. 6 is, with respect to traditional soft decoder, provides the required hardware cost of multistage output sampling can obtain suitable saving.
When receiving packet data, the multistage output sampling value of all soft or half-soft descrambler will have identical symbol.For reducing the influence of the random error in this output sampling value, this output sampling value is by comb filter module 407 and by average.The embodiment of comb filter is shown among Fig. 7 and Fig. 8.
Please refer to Fig. 7 now, the real part of the data symbol 701 of input and imaginary part are input to multiplier 705 and by weights W
1Weighting in addition.Utilize a Delay Element 704 and an adder 703 and output signal 702 after being added to the delay of feedback through the signal of weighting.Before with this feedback loop output signal and this input signal addition, the feedback signal after the delay also uses multiplier 706 with by weights W
2Weighting in addition.
According to a specific embodiments, the data symbol 701 of input is to be multiplied by 0.2 fixing point equivalence value by multiplier 705, and delayed " on average " value system that Delay Element 704 is provided is multiplied by 0.8 fixing point equivalence value.Though this algorithm of this embodiment is to describe with reference to 0.2 and 0.8 weights respectively, those of ordinary skills can understand this weighting algorithm can utilize various weights combination W
1With W
2And reach same effect.The noise of this input sampling value 701 reduces effect can be by reducing weights W
1Value and increase W
2Value and strengthen.Relatively, the correctness that in time receives data symbol can pass through to increase by the first weights W
1Value and reduce by the second weights W
2Value and strengthen.
The another kind of embodiment of comb filter framework is shown among Fig. 8.The mean value that n the small-pulse effect that each output representative of shown this comb filter that goes out is separated by 11 or 22 samplings (depending on applied input sampling rate) taken a sample.Understand that as those of ordinary skills the quantity of average sample can suitably be set to reach enough noises and reduce effect.When increasing the number of n, will more effectively reduce noise.In the particular example of this embodiment, the quantity n of average sample is 10.The mean amplitude of tide of same-phase channel I and quadrature phase channels Q is independent calculating.This can implement following formula and reach in this specific embodiments:
Wherein f (k) represents the output of this comb filter, and the output of this decoder of d (k-22i) representative when using the Barker sequence of 22 samplings, as above-mentioned.
The output f of filter
IAnd f
QAll will be used for determining whether receiving at present package.In a specific embodiments, be the influence of this two output valve being counted mutually the frequency departure of this signal:
S(kT)＝f
I(kT)+f
Q(kT)
Wherein S represents the additive value of this two output valve, and f
IAnd f
QRepresent the mean value of output of the comb filter of this passage out of the ordinary.
Please turn one's head now with reference to figure 8, comb filter 800 comprises a plurality of Delay Elements 804, an adder 803 and a divider 805.The decoder output of being imported 801 is input to this adder 803 and more inputs to first assembly of these Delay Elements identical from one another 804.The output of each Delay Element 804 all inputs to this adder 803, and inputs to the input of next Delay Element 804.This adder 803 receives the input signal of n predetermined quantity, and those input signals are accumulated and inputed to this divider 805.The quantity n of input and the correlated measure n-1 of Delay Element 804 set according to aforementioned consideration.The summation that 805 pairs of these adders 803 of divider are provided is carried out standardization.
Fig. 9 demonstrates the example that how to detect package in the incoming traffic signal.After receiving this communication signal (step 900), this communication signal is subjected to soft decoding processing (step 901), and decoded output is smoothed to reduce the influence (step 902) of the random error in this communication signal.In step 903, this package is detected in this output signal according to this output signal value of level and smooth decoder output.Preamble detection is by relatively the output and a predefined threshold value of this comb filter are carried out.Thresholding controller 408 performed details of operations will be illustrated among Figure 10.
As shown in Figure 10, the summation S (step 1001) of resulting each comb filter ties up to and compares with predefined threshold T h during package is searched, shown in step 1002.When the output of this comb filter during, can be considered and detect a package (step 1003), and this preamble detection operation enters into " preamble detection state " greater than this predefined threshold T h.Whether this thresholding controller 408 will be maintained in this state, can be bigger with the output that determines follow-up decoder but extract two small-pulse effects again.
After comparing two other sampling value, this thresholding controller will periodically be confirmed this comparative result, that is to say, knack fixes on the peak value whether symbol duration can occur decoder afterwards once again.Before clearly declaring to detect package, the output of this comb filter must surpass pre-determined number (step 1004,1005) greater than the number of times of this predefined threshold T h.This comparator results in step 1002 had been confirmed pre-determined number T
NAfterwards, then enter this " blocking " (in the situation that detects package).In one embodiment, T
NBe 15, that is to say, must affirmation detect package 15 times.Those of ordinary skills also can use arbitrarily other number of times reaching same effect as can be known, such as, T
NBetween 10 to 20 times.
According to this IEEE802.11b standard of WLAN, this thresholding controller 408 can be used for detecting long and short package.Because these two kinds of packages are not only variant on length, this binary value of this preamble sequence also is different, can utilize relevant for the different threshold values of this binary system package value and distinguish these packages.
The compare operation of growing with the thresholding of lacking package that can detect according to this WLAN standard is illustrated among Figure 11.This preamble detection procedure employs first threshold T h
1And the second threshold T h
2According to desired decoder output valve+1/-1, this two threshold value is just different on sign symbol.
In step 1102 or step 1107, detect earlier after the long or short package, each package is repeatedly carried out " marginal testing " of step 1103-1106 or step 1108-1111.Can't confirm to be in long package at the length that is detected or short package and confirm that this threshold compataror skips back to step 1101 in a certain circulation of the step 1103-1106 of operation or the formed affirmation circulation of step 1108-1111 that short package is confirmed operation.
Detecting package and affirmation, and after the symbol time of advent and the timing skew of symbol between the processing time in known next data module, this symbol synchronizer module 403 will discharge data makes call sign release can be matched with the symbol processing.
According to each above-mentioned embodiment, definite result of each symbol of being sent is moved to the output of this comb filter by the output from this demodulator.According to a specific embodiments, use a medium-soft decoder, this half-soft descrambler imports binarization operation in " delay path " of this decoder that comprises a plurality of 1 bit width buffers.This half-soft descrambler is output as a sequence of soft-symbols that is arranged in desired value+1 (by the 1 long package of being sent of being formed) or-1 (by the 0 short package of being sent of being formed) according to the preamble sequence of being sent.
The above embodiments can provide more reliable and obtain improved preamble detection ability, but can not increase hardware complexity.Follow-up the processing stage, the preamble detection of each above-mentioned embodiment can reduce the occurrence rate that can't detect package or detect package mistakenly by this preamble detection step is moved to.
Though the present invention discloses as above with a preferred embodiment; right its is not in order to limit the present invention; anyly have the knack of this skill person; without departing from the spirit and scope of the present invention; when can doing a little change and retouching, so protection scope of the present invention is as the criterion when looking accompanying the claim person of defining.
Industrial usability
Obviously, the present invention benefits and uses on industrial process and product.
Claims (10)
1. a Sychronization data detection unit is used for detecting the predetermined synchrodata in the transmission frame in the communication signal in a communication system, and this synchrodata comprises an identical binary symbol sequence of encoding and afterwards transmitting earlier, and this Sychronization data detection unit comprises:
One decoder (406), this communication signal (501) of being received and generate the dateout symbol (502) with multilevel signal value is used to decode;
One filter (407) is used for level and smooth decoded this dateout symbol (502); And
One threshold device (408), be used for the output (802) and a predetermined threshold (Th) after level and smooth of this filter (407) relatively, if this output (802) of this filter (407) surpasses this predetermined threshold (Th), then this threshold device is indicated the testing result of this synchrodata.
2. as claim 1 a described Sychronization data detection unit, wherein this decoder (500) comprising:
Binarization is (503) partly, convert the multistage input signal (501a) that is received to binary signal;
Postpone partly (504-506), postpone this binary signal according to predefined decoding rule; And
Multiplication is (502) partly, and this multistage input signal (501b) is multiplied by this binary signal that this delay part (504-506) is exported, and export a decoding back signal.
3. as claim 2 a described Sychronization data detection unit, wherein this delay part (504-506) comprises a plurality of delay zones (504,505) and at least one signal merge partly (506), this signal merges partly and merges the binary signals with different delays according to predefined decoding rule.
4. as claim 2 a described Sychronization data detection unit, wherein should postpone part (504,505) and comprise a plurality of delay time registers (601-606), each delay time register (601-606) has 1 width.
5. as claim 1 a described Sychronization data detection unit, wherein has at least 2 width through this signal output of decoding.
6. one kind in order to detecting the method for the predetermined synchrodata in the transmission frame in the communication signal, and this synchrodata comprises an identical binary symbol sequence of encoding and afterwards transmitting earlier, and this method comprises the following steps:
The step of the dateout sequence that this communication signal that decoding (901) is received and generation have the multilevel signal value;
Smoothly (902) are through the step of this multilevel signal value of decoded this communication signal; And
Relatively (903) through this multilevel signal value of level and smooth back signal and the step of a predetermined threshold value (Th), and if after should be level and smooth signal then represent the step that has detected this synchrodata above this predetermined threshold (Th).
7. as the method for the predetermined synchrodata of claim 6 a described detection, wherein this decoding step (901) comprises the following steps:
This multistage input signal that is received is converted to the step of binary signal;
Postpone the step of this binary signal according to predefined decoding rule;
This multistage input signal is multiplied by the step of this binary signal; And
Export the step of this decoding back signal.
8. as the method for the predetermined synchrodata of claim 7 a described detection, the step that wherein postpones this binary signal comprises the following steps:
Postpone this binary signal and will postpone the binary signal merging that back binary signal and further postpones according to this predetermined decoding rule.
9. as the method for the predetermined synchrodata of claim 6 a described detection, wherein this comparison step (901) further comprises:
Determining that (1001-1005) follow-up accumulation results surpasses this predetermined threshold (Th) and reaches pre-determined number (T
N) afterwards, indication detects the step of synchrodata.
10. as the method for the predetermined synchrodata of claim 9 a described detection, wherein this comparison step further comprises the following steps:
With this accumulation results be used to detect the first threshold value (Th of long synchrodata of length
1) compare (1104); And
With this accumulation results be used to detect the second threshold value (Th of short synchrodata of length
2) compare.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE10214063A DE10214063B4 (en) | 2002-03-28 | 2002-03-28 | Synchronization data detection unit and method |
| DE10214063.4 | 2002-03-28 | ||
| US10/259,717 US6909760B2 (en) | 2002-03-28 | 2002-09-27 | Sychronization data detection unit and method |
| US10/259,717 | 2002-09-27 |
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| CN1643838A true CN1643838A (en) | 2005-07-20 |
| CN100367698C CN100367698C (en) | 2008-02-06 |
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| EP (1) | EP1488565A1 (en) |
| JP (1) | JP4191612B2 (en) |
| CN (1) | CN100367698C (en) |
| AU (1) | AU2003217841A1 (en) |
| TW (1) | TWI251421B (en) |
| WO (1) | WO2003084119A1 (en) |
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| DE10214063B4 (en) * | 2002-03-28 | 2007-05-03 | Advanced Micro Devices, Inc., Sunnyvale | Synchronization data detection unit and method |
| ATE413040T1 (en) * | 2003-06-25 | 2008-11-15 | Nxp Bv | FRAME FORMAT DECODER AND TRAINING SEQUENCE GENERATOR FOR WIRELESS LOCAL AREA NETWORK |
| US7522677B2 (en) * | 2003-10-21 | 2009-04-21 | Texas Instruments Incorporated | Receiver with low power listen mode in a wireless local area network |
| AU2006211037B2 (en) | 2005-02-07 | 2012-05-24 | Roche Glycart Ag | Antigen binding molecules that bind EGFR, vectors encoding same, and uses thereof |
| ES2326054B1 (en) * | 2006-04-04 | 2010-07-05 | Diseño De Sistemas En Silicio S.A. | PROCEDURE FOR SIMULTANEOUS TRANSMISSION IN TIME AND FREQUENCY OF MULTIPLE DATA COMMUNICATIONS THROUGH MODULATIONS OFDM. |
| US8265056B2 (en) * | 2008-02-19 | 2012-09-11 | Qualcomm Incorporated | Packet decoding for H-ARQ transmission |
| US8179920B2 (en) | 2008-09-11 | 2012-05-15 | Entropic Communications, Inc. | High efficiency preambles for communications systems over pseudo-stationary communication channels |
| CN108480415B (en) * | 2018-03-20 | 2020-03-24 | 中冶赛迪工程技术股份有限公司 | Online rolling thermoforming process for hot plate/belt and application of online rolling thermoforming process |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| FR2493646A1 (en) * | 1980-10-31 | 1982-05-07 | Thomson Csf | Synchroniser for analogue modulation transmitted data - operates on digital information samples rectified analogue signals at rate varied according to summation of various sample group amplitudes |
| WO1995010903A1 (en) * | 1993-10-14 | 1995-04-20 | Ntt Mobile Communications Network Inc. | Correlation detector and communication apparatus |
| US5982807A (en) * | 1997-03-17 | 1999-11-09 | Harris Corporation | High data rate spread spectrum transceiver and associated methods |
| KR100244190B1 (en) * | 1997-08-29 | 2000-02-01 | 구자홍 | Sync. signal detection circuit |
| US6226336B1 (en) * | 1998-02-20 | 2001-05-01 | Telefonaktiebolaget Lm Ericsson (Publ) | Method and apparatus for detecting a frequency synchronization signal |
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2003
- 2003-02-28 WO PCT/US2003/006259 patent/WO2003084119A1/en active Application Filing
- 2003-02-28 JP JP2003581399A patent/JP4191612B2/en not_active Expired - Fee Related
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- 2003-02-28 AU AU2003217841A patent/AU2003217841A1/en not_active Abandoned
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| EP1488565A1 (en) | 2004-12-22 |
| JP2005522093A (en) | 2005-07-21 |
| AU2003217841A1 (en) | 2003-10-13 |
| JP4191612B2 (en) | 2008-12-03 |
| TW200306730A (en) | 2003-11-16 |
| WO2003084119A1 (en) | 2003-10-09 |
| CN100367698C (en) | 2008-02-06 |
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