TW201105074A - Method of generating preamble sequence for wireless local area network device - Google Patents

Abstract

A method of generating preamble sequence for a wireless local area network device includes generating a first frequency-domain preamble sequence according to information of a packet to be transmitted, wherein the first frequency-domain preamble sequence includes a plurality of subsequences corresponding to a plurality of sub-channels, adjusting a phase of each subsequence of the first frequency-domain preamble sequence for generating a second frequency-domain preamble sequence, transforming the second frequency-domain preamble sequence into a first time-domain preamble sequence, performing a cyclic shift delaying process on the first time-domain preamble sequence for generating a plurality of delayed time-domain preamble sequences, and normalizing on the plurality of delayed time-domain preamble sequences for generating a second time-domain preamble sequence that is a preamble of the packet to be transmitted.

Description

201105074 VI. Description of the Invention: [Technical Field] The present invention relates to a method for generating a Preamble sequence of a wireless local area network device and related devices, and more particularly to an indication for the 8正211 There is no deduction standard __ Occupation _ set (four) phase generation method and related devices. [Prior Art] Wireless Local Area Network (WLAN) technology is one of the popular wireless communication technologies. It was first used in military applications and has been widely used in various consumer electronic products in recent years, such as desktop computers and notes. A computer or personal digital assistant that provides the convenience and speed of Internet communication for the general public. The IEEE 802.11 series of wireless LAN protocols is developed by the Institute of Electrical and Electronics Engineers (IEHE) and evolved from the early positive 802.11a, positive EE802.Ub, and positive EE802.llg. Up to now the mainstream ffiEE 802.11η. IEEE 8GZlla/g/n standard 胄 uses orthogonal frequency division &

Frequency-Division Multiplexing (OFDM) modulation technology, unlike the positive he 802.11a/g standard, the IEEE 8〇2·1ΐη standard uses Multiple Input Multiple Output 'ΜΙΜΟ technology and other new functions. Improved data rate and throughput (Throughput)' At the same time, the channel bandwidth is increased from 20MHz to 40MHz. Please refer to Figure 1, the first picture shows the packet format of the conventional 802.Πη standard. 201105074

intention. As shown in Figure 1, the 802.11n standard packet is composed of a pre-prepared data (Preamble) and the data to be transmitted. The pre-data is located at the forefront of each packet and is connected to the data to be transmitted. In addition, the pre-data is a mixed format, which can be compatible with the IEEE802.11a/g standard wireless local area network device, and the fields included are the traditional short training field L-STF (Legacy Short Training Field). L-LTF (Legacy Long Training Field), L-SIG (Legacy Signal Field), HT_SIG ( ffigh-ThroughPut Signal Field), high throughput short training HT_STF (High-Throughput Short Training Field) and N high-through-long training field HT-LTF (High-Throughput Long Training Held). The traditional short training field L-STF is used for start-of-packet detection, automatic gain control (AGC), initial frequency offset estimation (Frequency Offset Estimation) and initial time synchronization (Time). Synchr〇nizati〇n); the traditional long training field L-LTF is used for precise frequency offset estimation and time synchronization; the traditional signal blocking L-SIG carries information on data rate and packet length. High-throughput signal interception HT-SIG carries data rate information 'and is used to automatically detect packets in mixed or traditional formats, 咼 short throughput training field HT-STF for automatic gain control; and high throughput long The training block HT-LTF is used for channel estimation of multiple input and multiple output. According to the current EEEE 802.11 η standard, in the 40MHz channel pre-data, the second half of the 20MHz channel pre-data is the same as the 802 802·丨丨吮 standard packet pre-data, the upper half of the 20MHz channel pre-data It is copied from the 2nd MHz channel of the lower half and the phase is rotated by 90. This can reduce the peak-to-average power ratio when the signal transmitting end transmits the front-mounted 201105074 bedding material, and improve the probability that the signal receiving end successfully detects the packet. Referring to FIG. 2, FIG. 2 is a functional block diagram of one of the wireless transmitter systems of the four-four-four-receive (T4R) wireless communication system of the conventional IEEE 802.11n standard. The signal transmitter 20 includes a signal conversion unit 2, a cyclic shift delay s touch Delay 'CSD) processing unit ~ CSD_3, a guard interval ((4) brewing j, GI) processing unit GI - a heart-to-heart RF processing unit welcomes" ~where - 4 and antenna ~ Μ 'each of each cyclic shift delay processing unit, tilt interval processing unit, RF unit ^ unit and antenna combination ' _ - miscellaneous chain (TYansmitChain). The signal is rotated, and the unit 200 is used to perform inverse discrete Fourier transform (inverse Discrete F〇urjer Transform) to implement orthogonal frequency division multiplexing modulation, and the frequency domain (FrequencyD〇main)

The round-in sequence is converted into a time domain (Tlme D〇main) orthogonal frequency division multiplexer (〇FDM ymbol) sequence. In terms of data, the frequency domain input to the signal conversion unit can be used to set the data field of the fixed value, such as traditional short training booth, traditional long training position, high throughput _ training or high. The amount of material is likely to be used, or it can be used for the processing of the bar, such as the traditional signal field or the high-throughput signal field. As shown in Figure 2, the frequency domain pre-data sequence is converted to the pre-domain (4) phase Sn by the signal conversion unit 2, and then the transmission chain is cyclically shifted and the processing unit CSD_x is added. Cydie piefix anti-multipath round channel interference 'pass-protection interval processing unit, in the pre-data sequence ~ 32 off 64 _ time length as a guard interval to resist inter-symbol Interference It is converted to an RF signal by an RF processing unit RF_X; finally, it is transmitted by an antenna 至 to a signal receiver. In order to achieve higher quality wireless LAN transmission, the relevant units are developing a new generation of 802.11 ac standard 'very high throughput (VHT) wireless local area network standard' channel bandwidth by 4〇 The mHz is increased to 80MHz. If the downward compatibility is used in the IEEE 802.11n standard, the data of the lower half of the 4 〇mHz channel is copied and the phase is rotated by 9 〇. , the upper half of the 4 〇 mHz channel pre-data is generated, so the peak-to-average power ratio (Peak-to-Average P〇wer Rati〇) of the obtained 80 MHz channel data will be very high, affecting the transmission of the packet. quality. Therefore, the IEEE 802.11ac standard should not only be compatible with the wireless local area network device of the EE8〇2 lla/g/n standard, but also improve the transmission quality of the packet. SUMMARY OF THE INVENTION The main purpose of this is to provide a view of the wireless local area network device pre-data sequence generation method and related devices, so that the standard of curry

It is compatible with the IEEE802.11a/g/n standard wireless local area network device, and 7" and improves the transmission quality of the packet. W wireless local area network The present invention discloses a pre-data sequence generating method for generating a-packet-pre- (four) sequence in a system, and the wireless area network channel is deleted according to the 'before'. - a first-frequency domain preamble sequence, the first-frequency domain pre-sequence sequence 201105074 includes a complex side domain preamble: a hetero-subsequence sequence, corresponding to _ a plurality of sub-channels; adjusting the j-frequency domain 赖#料相巾- _ pre-positioned the dragon to paste her to generate a second „frequency domain pre-data sequence; the second-frequency domain pre-data sequence is converted into a first: time domain pre- (four) sequence; the first pre-order ship The Puhuan shift delay processing domain regenerates the domain pre-data phase; and performs a credit operation on the plurality of delayed time domain pre-data phases to generate a second second-machine pre-data sequence as the packet The preamble data sequence. The invention further discloses a preamble data sequence generating device, which is used for generating a packet-pre-data sequence in a wireless local area network system, and one channel of the wireless area network system includes a plurality of sub-channels Channel, bribe data sequence generating device Having a sequence generating unit 用来' for generating a first frequency domain preamble sequence according to the information of the packet, the first frequency domain preamble sequence comprising a plurality of frequency domain preamble subsequences corresponding to the complex number a sub-channel; a phase adjustment unit that breaks the phase of each of the frequency domain preamble subsequences in the first-frequency domain preamble sequence to generate a second frequency domain preamble sequence; a signal conversion unit, And converting the second frequency domain preamble sequence into a first time domain preamble sequence; and a peak-to-average power ratio adjustment unit for reducing a peak-to-average power ratio of the transmission power of the first time domain preamble sequence To generate a second time domain preamble sequence 'as the preamble sequence of the packet. [Embodiment] Referring to FIG. 3, FIG. 3 is a fourth embodiment of the IEEE 802.11ac standard according to an embodiment of the present invention. The function block diagram of the signal transmitter 30, which is one of the wireless communication systems. The signal transmission 201105074 can be used for the wireless area network card, the wireless area network access point (A (10), etc.), the computer and the mobile base Mobile phone or personal digital assistant, etc. The job conveyor % includes a sequence generating unit 3, - phase adjusting unit 3 〇 2, a signal converting unit 3 〇 4, - peak mean power _ whole unit 3G6, cyclic shift delay processing Unit CSD ^ ~ CSD_3, guard interval processing unit GL1 ~ GI - 4, radio frequency processing unit - "two traits * = antennas A1 ~ A4," per-cycle shift delay processing unit, guard interval processing unit, radio frequency processing unit and antenna Forming a transmission chain. The combination of the sequence generation unit το 300, the phase adjustment unit 3〇2, the signal conversion unit 3〇4, and the peak-to-average power ratio weaving unit 3G6 can be regarded as a “time domain pre-data sequence generating device” The time domain preamble sequence is the orthogonal frequency division multiplexer (symb〇1). The signal conversion unit converts the preamble sequence from the frequency domain to the time domain. The peak-to-average power ratio adjustment unit 306 further includes cyclic shift delay processing units CSDA_1 CSCSDA-4, multipliers M1 to M4, and an adder 31A. The 80MHz channel used in the EE 802.11ac standard can be divided into four 2〇MHz subchannels. The pre-war data sequence of the 8GMHz channel is generated by the pre-ship unit filaments. The frequency domain preamble sequence of the three 2〇MHz subchannels with higher frequency bands is the frequency domain preamble sequence copied from the lowest 20MHz subchannel of the frequency band. , that is, one of the 802.11a/g standards, a frequency domain preamble sequence of 2 〇 mHz channels. Since the 20MHz channel of the Zhengqiu 802.11a/g standard contains 64 subcarriers, the frequency domain preamble sequence of the 2〇MHz channel is represented as j = 0, l, .,, 63}, therefore, the sequence generating unit 3〇 The frequency domain preamble sequence generated by the 8〇MHz fill is 201105074 {*^=\m〇d64,々= 0,l”..,255}. Before the IEEE 802'llac standard, the data column is set. Among the bits, the traditional short training field L STF traditional long training field L_LTF, high throughput short training block hT_stf and high throughput long training block HT_LTF are fixed values, stored in the signal transmitter 3〇 = memory ( Not shown in Fig. 3) 'Therefore' the sequence generating unit 3 is directly taken from the memory, and the 20 MHz sub-channel pre-data sequence is known to generate the data of the 2 channels before the data. On the other hand, the traditional signal interception B_; 51 (3 and high-throughput signal field HT-SIG non-fixed value 'but carries information such as data rate and packet length, so 'traditional signal interception L-SIG and high The data sequence of the 2〇mhz subchannel of the 呑 量 信号 & HT_SIG is first corrected by forward error Signal processing programs such as coding (F〇rward Err〇r CorrectionEncoding), interleaving (interleaving), and binary phase shift keying (Binary Phase Shift Keying) are output to the sequence generating unit 300, and the above signal processing program It is well known to those skilled in the art and will not be described in detail herein. The phase adjustment unit 302 is lightly connected to the sequence generating unit 3, implemented by a multiplier, and is used to phase the frequency domain preamble sequence of the 80 MHz channel. Adjusting, in the frequency domain preamble sequence of the three 20MHz subchannels with higher frequency bands, the phase of the data domain of each 2〇MHz subchannel is the frequency of the 20MHz subchannel of the adjacent lower frequency band. The phase of the domain preamble sequence is rotated by 90. In other words, the phase of the frequency domain preamble sequence of the other 20 MHz subchannel is rotated relative to the phase of the frequency domain preamble sequence of the 20 MHz subchannel of the lowest frequency band. 90, 180, 270. The angle of rotation required for the phase of the frequency domain preamble sequence of each 20 MHz 201105074 subchannel is also stored in the memory of the signal transmitter 30, phase The whole unit 302 obtains the rotation angle corresponding to each 2〇miJ subchannel from the memory to adjust the frequency domain preamble sequence generated by the sequence generating unit 3〇〇 to an appropriate phase. The phase adjustment unit 3〇2 outputs The frequency domain preamble sequence is expressed as follows: A = (#/64"&m()d64,^: = 〇,1,.··,255. (1) φ Please refer to FIG. 4, which is a schematic diagram of an 80 MHz channel preamble sequence in the frequency domain in the IEEE 802.11ac standard packet according to the embodiment of the present invention. The pre-data sequence shown in Fig. 4 is the 8 〇mHz channel pre-sequence data sequence after the phase adjustment unit 302 rotates the phase. The lowest frequency 20 MHz sub-channel pre-data sequence 歹 ij{& moxibustion =0,1,".,63} is represented by S, so the four 20MHz sub-channel pre-data sequences are S, jS, S, and JS according to the frequency band from low to sequential. It can be clearly seen from Fig. 4 that the pre-data sequence of each 20 MHz sub-channel is 90 different from the phase of the pre-data of the 20 MHz sub-channel adjacent to the lower frequency band. Therefore, the pre-configuration data shown in Figure 4 can be backward compatible with the 20MHz channel of the IEEE 802.11 a/g standard or the 40MHz channel of the IEEE 802.11n standard. The signal conversion unit 304 is coupled to the phase adjustment unit 302 and operates in the same manner as the signal conversion unit 200 of the signal transmitter 20 in FIG. 2 for performing inverse discrete Fourier transform to replace the frequency domain preamble data with the time domain. Set the data sequence {\^ = 〇, 1, ..., 255}, that is, the orthogonal frequency division multiplexed modulation symbol. The conversion by the signal conversion unit 304 is expressed as 11 (2) 255. 201105074

Sn = k^〇 According to Equation 1 and Equation 2, we can get 255.2 π f^ = Σ k=0 63 Σ^·[^ + , A:=〇63 ·[ 1 + e^2' + e Λ=0 4. /.赛如64)" + γ v_&("128)" + ν·δ^Η yf(«+i); ρΜ«+ι) + ^/γ("+1) (3) 3. When the sampling time n takes the remainder of 4, the result is equal to 0, 1, 2, 3 (1 + #+1) + W«+1) + #+1)) respectively n = 0:\l + ej ^n+l) ^eMn+l) +ej^{n+l) \ n = l:(l + ej^n+l) +eMn+l) +^(Λ+1) \^ej^+ejn +ej~2 (l + ejn + ej2% + ej 3π \ 0 J3π)=ο n 2: fl + eJ^(n+l) + eJ^n+x) + J^n+l>> f : 3π ., .* 9π \l+〆2 + θ4π + 〆2 1 = o (l + ^'27I+e74it+e7'67t)=4 (4) Inductively know that \ + ej^n+l) + eMn+ l)-^ ej3^n+^ v 0, if wmod4 = 0,1,2 4, if wmod4 = 3 (5) From Equation 3 and Equation 5, the time domain preamble sequence generated by the signal conversion unit 3〇4 is known. {~, "= 0,1,.",255}, there are three-quarters of the data value is 〇, so that 12 201105074 ::= peak-to-average power ratio adjusts the cyclic shift delay in the private view Processing unit=SDSTTA—4 The ring-shifting gorge element is input to the signal conversion sequence ^ s, s, s. The delay time of the cyclic shift delay processing unit c is different from each other, and is sequentially different, 4 咐 4, 255 Σ^β7256 (n+4mi) ^ ^(2) _ ye^ A («+4/7i2+l) (4) t, k ^ value non-only-solution 'can be summarized slave, its towel%, call, ton, called a positive integer, can be the same or different values. According to Equation 2 and the above-mentioned delay date, the cyclic shift delay processing unit CSDAj~CSDA_4 is divided into & capable (four) sequences ... 255 ... _

S

255 〇S(3) = ^skeJ^k(n+4m2+2) k—0 255 and *s(4) = aged coffee +4w4+3) k=0 2π multiplier ~M4 and adder 310 The normalization (N〇mi this sum) operation is performed to maintain the transmission power of the preamble sequence unchanged. The multipliers m1 to M4 are used to multiply the pre-set data sequences S(1), S(2), S(3), and S(4) by the cyclic shift delay processing unit CSDA_KSDA-4, respectively, to correspond to corresponding ones. The normalization coefficient is still P2, P3, and P4. The present invention does not limit the normalization coefficients P1, P2, P3, and P4 to a specific combination. Under the condition that the transmission power is constant, each normalization coefficient can be freely set to (4) 31 () secret to the multipliers M1 to M4 for multiplication. The multiplication results generated by the devices M1 to M4 are added to generate 13 201105074. The amount of data of a pre-data sequence passing the peak-to-average power ratio of 1 〇, ^^ = +/?2J (3) +#(4)^ = 0^, , 255). When the adjustment unit is operated, the number of data whose value is 0 in the pre-data sequence & is greatly reduced, and the number of pre-arranged data sequences & output by the parent-child signal conversion unit 304 is greatly reduced. Decrease, so the peak-to-average power ratio of the pre-data sequence *^ produces a pre-data sequence than the peak-to-average power ratio adjustment unit 3〇6 (following, the cyclic shift in the chain also delays the processing unit Na-Bu (4)” and protection The interval processing is earlier than GI"~GI-4, and the signal processing against multipath interference and inter-interference interference is performed and converted into an RF signal by the radio processing unit, that is, the "4", and finally the antenna A4 & The operation of the transmission chain of the signal transmitter 30 is the same as that of the conventional IEEE 802.11 transmission chain of the standard signal transmitter, and will not be described here. The IEEE 802.11n standard signal transmitter in FIG. In 20, the pre-data sequence of the 20 MHz or 40 MHz channel is processed after being converted into a time domain pre-lean sequence by the signal conversion unit 2, and then output to each transmission chain for processing. In the embodiment of the present invention, the IEEE 802.11ac standard In the signal transmitter 30, the frequency domain preamble sequence of the 80 MHz channel not only passes through the phase adjustment unit 302 but also the higher frequency of the three 20 MHz subchannels before passing through the signal conversion unit 3〇4. The pre-data sequence is rotated to the appropriate phase' to form a pre-growth sequence as shown in FIG. 4, and after being converted into a time-domain pre-data sequence by the signal conversion unit 304, further through the peak-to-average power ratio adjustment unit 14 201105074 Yuan Hao, lowering the peak power of the transmission power than the channel before the data can not only be backward compatible = quasi-, and its peak mean value can also be satisfied with her. Please refer to Figure 5A and 5B Fig. : Mean: rate_single, signal conversion==: the average value of the material is over the peak value of the solution. The 8G®mn^ material value of the material is compared with the time, which is the cyclic shift delay processing. The delay time of the unit-~CSDA-4 is set according to mi=m2=m3=%=〇, and the normalized coefficient ΡιTM=7ϊ' used by the path multipliers M1 to M4 is set to be close to u. Therefore, the whole 3〇6 can make the 80ΜΗζ value of the sheep significantly lower than the adjustment of the early morning.... The clearing value of the power is higher than that of the transmitter, which is an embodiment of the invention, and the field is generally known to change and modify. For example, phase adjustment unit 302 '' The phase rotation angle stored in the memory of the machine _3 — — — — 工 工 工 工 工 工 工 工 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位 相位The adjustment unit 302 generates =!? is no longer equal to the pre-sequence data sequence shown in FIG. 4, and the number of data of the signal conversion table is 40. The difference is different, so the 'study average power ratio adjustment unit 鄕 may need to include 3 different numbers of cyclic shift pro-processing units and corresponding multipliers to achieve the effect of reducing the peak-to-average power ratio. In order to verify the signal of the wireless area Na system, Wei Weizheng measured the 8_channel #聪4, the 3rd figure shouting transmission (4) of the present invention, and simulated the channel environment as Xie _ quasi-channel model B ( Ch coffee d Model B). The signal transmitter 30 transmits 1 〇〇 (H solid only contains 8 ramie channel pre-data packets, 4 ζ ζ channel city connection (4) and 8_z channel signal receiver receives and calculates the correct _ packet rate, in Figure 6 to Figure 9. The 80MHz channel can be divided into 4 non-overlapping 2_z subchannels, with the frequency band from low to high being A, B, C, D; 80MHZ channel can be divided into 3 partially overlapping 4 〇MHz sub-channels {A, B}, {B, C}, and {C, D}. Figure 6 shows one of the 40MHz channels, one of the receivers, Auto-correlation Detector, at each 40MHz sub-channel. Channels {A, B}, {B, c}, {C, D} and under each transmission chain, based on different signal-to-noise ratios

Ratio ' SNR ) The minimum value of the packet detection probability (PacketDetecti〇n Probability). The 7th chart shows the cross-correlation Detector of the signal receiver of the 4〇MHz channel. Under each of the 40MHz sub-compasses {A, B}, {B, C}, {C, D} and each transmission chain, the packets detected based on different signal-to-noise ratios successfully detect the minimum probability. It can be seen from Fig. 6 and Fig. 7 that the minimum detection probability of the packet detected by the signal receiver of the 40 MHz channel is 201105074. This is not the case that the signal receiver does not support the iEEE8〇2.ilac standard; The signal receiver can also successfully detect the pre-sequence data sequence of the 80 MHz channel generated by the signal transmitter 30. The 8th chart column 8 is one of the channels. The signal is connected, and the machine-autocorrelation _ is used under each side of the special transmission chain. The minimum rate of success is based on different signal-to-noise ratios. The ninth table lists the 8QMHz channel. The one-signal receiver-interaction correlation detector is used under each transmission key to detect the minimum probability of the packet based on the different signal-to-noise ratio. From Fig. 8 and Fig. 9 φ, it can be seen that the maximum value of the packet side rate measured by the signal receiver of the 8 〇 MHz channel is mostly 1 GG%, which indicates the 8 sides generated by the signal transmitter 3 (). The z-channel pre-data sequence 'can be successfully detected by the signal receiver of the 8 〇 MHz channel. The sequence generating unit 3〇〇, the phase adjusting unit 3〇2, the signal conversion unit 304 and the peak-to-average power ratio adjusting unit 306 of the signal transmitter 30 operate according to a process to generate a time domain pre-data sequence, and output to the transmission. The chain is processed. Please refer to FIG. 1 , which is a schematic diagram of a process 4 实施 according to an embodiment of the present invention, and the flowchart 4 is used for! A signal transmitter of the 802.11 ac standard, such as the signal transmitter 3 of Figure 3, is used to generate a time domain preamble sequence of an 80 MHz channel as a pre-transmission sequence of data to be transmitted. The process 40 includes the following steps: Step 400: Start. Step 402: Generate a first frequency domain preamble sequence of 8 〇 MHz channel according to information of a to-be-transmitted packet. Step 404: Adjust one of each 20 MHz subchannel 17 of the first frequency domain preamble sequence. The phase of the frequency domain preamble sequence is generated to generate a second frequency domain preamble sequence of one of the 8 channels. ^406 · f The second _* preamble sequence is converted to a -first-time domain pre-depleted sequence. And 8 performing a cyclic shift delay on the first time domain preamble sequence, and generating N delayed time domain preamble sequences. /Step 41〇.= The N delayed time domain preamble sequences are normalized to generate a second time domain preamble sequence as a preamble sequence of the to-be-transmitted packet. Step 412: End. The series of lions, before the test, sent to the news (four), here, the adjustment of the early 70 302 system according to the operation of step 404, the above two sub-adjustment unit 3G2 according to the four 2 〇 hall sub-channel from low to high paper phase The spin (four) degree is preferably Q. ,. Supervisor, Fertilizer Signal Conversion The Early Heart 4 Series' operates according to the step bar and can be expressed by Equation 2 above. The cyclic shift delay processing unit CSDA_i to csda-* of the peak-to-average power ratio adjusting unit 306 operates according to the step side. Due to the phase adjusted by the phase adjustment unit 3〇2, the first time domain preamble sequence is subjected to cyclic shift delay processing according to four different delay times to generate four delayed preamble sequences, such as the aforementioned SW and s. (2), s(3), s(4), used to reduce the transmission power scale average power ratio of the first-time domain preamble sequence. ♦ The multipliers M1 to M4 and the adder 31 of the mean power ratio adjusting unit 306 operate according to steps 41〇18 201105074, and finally generate a second time domain preamble sequence, which is compatible with IEEE802.11a. /g/n standard, with a preferred peak-to-average power ratio; pre-data sequence. It should be noted that the process 40 is not limited to use in the signal transmitter 30. Step 404 of flow 40 does not limit the use of a particular phase rotation angle. Further, step 4〇8 may correspondingly perform an appropriate number of cyclic shift delay processes in accordance with the phase adjusted in step 404 to reduce the peak-to-average power ratio. The present invention describes the phase of the pre-data sequence generating device and the rigid data sequence generating method according to the EE 802.1 lac standard, and the phase of the frequency domain preamble sequence of each 20 MHz subchannel in the 8 〇 mHz channel. Rotate the appropriate angle to make it downward compatible with the IEEE 802.11 a/g/n standard, and after the frequency domain preamble sequence is converted to the time domain preamble sequence, the operation of the cyclic shift delay is used to effectively reduce the time. The peak-to-average power ratio of the domain preamble sequence improves the transmission quality. The above are only the preferred embodiments of the present invention, and all changes and modifications made to the scope of the present invention should fall within the scope of the present invention. [Simple Description of the Drawing] Fig. 1 is a schematic diagram of a packet format of the conventional IEEE 802.11n standard. Figure 2 shows what Xi Zhi said! Ln fresh one of the signal transmitter block diagram. Fig. 3 is a block diagram of the function of the signal transmitter of the llae standard according to the embodiment of the present invention 201105074. FIG. 4 is a schematic diagram of an 80 MHz channel preamble data sequence in the frequency domain according to an IEEE 802.11ac standard according to an embodiment of the present invention. Fig. 5A is a schematic diagram showing the peak-to-average power comparison time of the transmission power of the 80 MHz channel preamble sequence obtained by the peak-to-average power ratio adjusting unit in the signal transmitter of Fig. 3. ~ Figure 5B is a schematic diagram showing the peak-to-average power versus time of the transmit power of the 80MHz channel preamble sequence obtained using the peak-to-average power ratio adjustment unit in the signal transmitter of Figure 3. Figure 6 shows the minimum detection success rate of the packet measured by the autocorrelation detector of one of the 40MHz channels in each 40MHz subchannel and each transmission chain based on different signal-to-noise ratios. List. Figure 7 is a list of the minimum detection success rate of the packets measured by the different ratios of the 4GMHz channel-signal receiver-interaction _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Figure 8 is a list of the small value of the successful side rate of the packet measured by the autocorrelation detector under one of the transmission channels of one of the 80 hall channels. The 80MHz channel-signal receiver-interactive phase__ is a list of packet success_minimum values measured under different transmission chains based on different signal-to-noise ratios. FIG. 10 is a schematic diagram of a process of an embodiment of the present invention. 20 201105074

[Main component symbol description] 20, 30 signal transmitter 300 sequence generation unit 302 phase adjustment unit 200, 304 signal conversion unit 306 peak-to-average power ratio adjustment unit 310 adder M1 to M4 multiplier CSD1 to CSD3 * CSDA_1 to CSDA-4 Cyclic shift delay processing unit GI-1~GI_4 guard interval processing unit RF-1 to RF_4 RF processing unit A1~A4 Antenna L-STF Traditional short training field L-LTF Traditional long training block L-SIG Traditional signal field HT-SIG High-throughput signal interception HT-STF High-throughput short training block HT-LTF High-throughput long training block Sk, sn, s, n, S, S (D, s(2), s(3), s(4) Pre-data sequence Pi, P2, P3, P4 normalization coefficient 40 Flow 400, 402, 404, 406, 408, 410, 412 Step 21 %

Claims (1)

201105074 VII. Patent application scope: 1. A pre-data (Preamble) sequence generation method for generating a pre-data sequence of a packet in a wireless local area network system, and one channel of the wireless local area network system includes a plurality of channels The sub-channel, the pre-data sequence generating method includes: generating, according to the information of the packet, a first frequency domain preamble sequence, where the first frequency domain preamble sequence comprises a plurality of frequency domain preamble subsequences, Corresponding to 5 sinusoidal subchannels; adjusting a phase of each of the frequency domain preamble subsequences in the first frequency domain preamble sequence to generate a second frequency domain preamble sequence; Converting the data sequence into a first time domain preamble sequence; performing cyclic shift delay processing on the first time domain preamble sequence to generate a plurality of delayed time domain preamble sequences; and delaying the plurality of delays The time domain preamble sequence is normalized (Νοπη-) to generate a second time domain preamble sequence as the additional data sequence of the packet. The method for generating a preamble data sequence according to claim 1, wherein the step of generating the first frequency domain preamble sequence according to the packet of the packet includes: according to the sentence, a message, generating a frequency domain Sampling a data subsequence corresponding to one of the lowest subchannels of the plurality of subchannels; and copying the preamble of the frequency domain to a frequency domain preamble corresponding to the other subchannels 22 201105074 Data subsequence 'to generate the first frequency domain preamble sequence. 3. The method according to claim 1, wherein the step of adjusting a phase of each of the frequency domain preamble subsequences in the first frequency domain preamble sequence is performed according to the plurality of subchannels The plurality of phase rotation angles adjust the phase of each of the frequency domain preamble subsequences in the first frequency domain preamble sequence. 4. The method according to claim 3, wherein the number of the plurality of subchannels in the channel is 4, and the phase rotation angle corresponding to the plurality of subchannels is 低 according to the frequency band from low to high. 9, 〇. 18〇. And 270. . 5. The method according to claim 1, wherein the step of performing cyclic shift delay processing on the first time domain preamble sequence is performed by using a plurality of different delay times. The time domain pre-data phase performs cyclic shift delay processing. 6. The method for generating a data sequence prior to the request item, wherein the plurality of delay time domain preamble sequences are normalized, the plurality of equal normalization coefficients are used, and the plurality of delay time domains are The data sequence is set to perform normalization operations. 7. - Light _ (Prea_e) sequence ship device for "None, Line Area System", first medium-one-package-pre-data sequence, the wireless area network system - channel contains a plurality of sub- The channel, the front surface sequence ship device includes: 23 201105074 sequence ί, the raw unit 'with fine sharp package: New, generated - the first frequency domain pre-buckle sequence 'the first - pro-previous data paste contains a plurality of frequency domain preamble subsequences corresponding to the plurality of subchannels; a phase adjustment unit that is difficult to generate a phase of each of the frequency domain preamble subsequences in the first frequency domain preamble sequence to generate a second a frequency domain preamble sequence; a signal conversion unit for converting the second frequency domain preamble sequence into a first time domain preamble sequence; and a peak-to-average power ratio adjustment unit, the wire lowering the first-time The peak-to-average power ratio of the transmit power of the domain preamble sequence to generate a second time domain preamble sequence as the preamble sequence of the packet. 8. Pre-arrangement sequence as described in claim 7 Generating unit According to the information of the packet, a frequency domain preamble subsequence corresponding to one of the lowest subchannels of the plurality of subchannels is generated, and the frequency domain preamble subsequence is copied into a frequency domain corresponding to the other subchannels. a pre-data subsequence to generate a first frequency domain preamble sequence. 9. The preamble sequence generating device according to claim 7, wherein the phase adjustment unit is based on a plurality of corresponding to the plurality of subchannels Phase rotation angle, adjusting the phase of each frequency domain preamble subsequence in the first frequency domain preamble sequence. 10. The preamble sequence generation device according to claim 7, wherein the channel includes 24 201105074 The number of complex good channels is 4, and the phase of the sub-channel touches the angle ,, according to the frequency band from low to high, 0, 9, 〇, 18 〇, and 27 〇, where the peak average power is 11. The term "pre-data sequence generation and loading adjustment unit" includes: a plurality of secret-bit delay processing units, reduced by the Wei number conversion unit, used The first-time financial data is processed in sequence to generate a plurality of delayed time domain preamble sequences; and the plurality of multipliers are used for a plurality of delayed time domain preambles and a plurality of regular numbers. The coefficients are multiplied to produce a plurality of multiplication results; and the demultiplexer is used to add the plurality of multiplication results to generate the second time domain preamble sequence. If the aim is U, the position of the ship is placed in front of the position, and several cyclic shifting delays are triggered by a plurality of delays. The first time domain pre-data phase is cyclically shifted. To generate the plurality of delayed time domain preamble sequences. 3_ The pre-set data sequence generating apparatus as claimed in claim U, wherein the plurality of normalized coefficients are equal. Eight, the pattern: 25