201008209 九、發明說明： 【發明所屬之技術領域】 本發明為一種適應性符元起始 法，特別是指透過計算符A的延遲相ϋ裝置與計算方 透過極性比對，能在頻率偏移值不定參數值， 元的起始點。 ^疋下仍可估測訊號符 【先前技術】 OFDM (正交頻分複用）系統因為為一種 (Multi-earner System )，其同步問題會比單載波還要重 要’所以任何的數位通訊系統中同步是不可缺少的操= 而若沒有射關步演算紐無料實地接㈣傳送的訊 號。而習知的同步方法有很多種，如使用訓練序列（介血㈣ sequence )保遵區#又方式（Guard_jntervai_Based，如美國 專利第6928048號）’或是利用領航訊號⑽〇 nal)的 方式。 在封包式傳輸的通訊糸統（packet-switching communication system)中，資料以封包為單位傳送，在傳 輸時，尤其是在接收到封包時，需同步化碼框與頻率的傳 輸’以偵測到是否有封包進來’此時需要一碼框同步電路 (frame synchronization circuit)找出特定符元的起始位 置，以便系統作訊號處理’如需要找到此封包式傳輸的通 訊系統用以估計通道的符元的位置，也就是用以估計通道 的符元的起始位置。 而在解調過程中，上述封包式傳輸的系統中的接收機 6 201008209 (receiver)是在時域上的任意點開始接收資料的，如應用 OFDM技術的通訊系統，其中調變是根據符元（symb^j) 的，所以接收機的第一個動作就是要檢測到符元的起始位 . 置（start P〇sition)，否則會因為符元的起始位置的誤差而 導致兩兩符元間的混淆，並造成符元判斷錯誤，此時就 要執行同步化。 在接收機接收到的資料中，設置有前置符元 (preamble)，其巾包括有重複出現的通道符元（如耐 ❹ symbol) ’此前置符元主要就是用於識別〇fdm系統的起 始位置，並用以進行通道估計（channelestimati〇n)，請夂 考第二圖所^習知OTDM系統接收機的電路方塊示意务 。。當OFDM訊號輸入此接收機1〇時，其中類比數位轉 =(ADC) 11轉換此類比訊號為數位訊號，並利用一個 符元起始點偵測器（symb〇lstartdetect〇r) 15债測轉換的 數位訊號中的起始點，並接著以FFTfn控制器17產生 由上述起始點位置的符元的快速傅利葉轉換（FFT)窗口 • !?δί1號’再依據1^窗口控制訊號，之後於類比數位 轉換器11轉換的喊上執躲速傅利葉轉換13。 此例、中，類比數位轉換器11將接收的訊號轉換為數位 ’並透過符元起始點偵測器15偵測到各符元的位置， • FF^f所，收的序列封包中的標頭（header)的起始位置， 資訊_、彳工制器I?則提供快速傅利葉轉換13的起始位置 貝§二以正確執行同步化與各訊號的傅利葉轉換。 圖，:參考第二圖所示一般0FDM系統之訊號結構示意 上述接收機所接收之訊號顯示如圖中的結構，如無 7 201008209 f個^區域網路（WPAN)的訊號結構，其中至少包括有 ，，符％部份（Preamble) 21，如標號1至24，另有標頭 23與資料部分25。各種通訊系統的訊號結構皆有特 ，規格（speciflcati〇n)，習知技術即應用符合特定的通訊 系統的訊號架構進行分析，以求得各訊號中的前置符元， 藉以準確進行通道估計與相關訊號的處理。 _ f例來說’在接收機輸出有意義的資料前，須透過不 同的廣异機制進行訊號處理，比如，可透過匹配手段 j matching )’利用符合特定規格的訊號形式與接收的訊號 二k不斷重複的比對，在一定門檻值的範圍内可得到前置 置。於解構出前置符元後，可準確得到標頭的起始 妓’如標號201的位置，即得出整個訊號的位置，可 接者執行通道估計。 【發明内容】 =行碼框同步找尋前置符元的技術中 與計算方法，能夠在頻率偏2 =付：°起始點計算裝置 付TL的方式，可省略 置或疋擷取 本發明所提出的適應：::：，。 用於各種封包是傳輸的通訊系統，藉由増 8 201008209 t遲^與設定多鱗數值的電路，讓碼框同步的效能不 θ輕易的叉到頻率偏移影響。 肺ίϊϊ的祕實施例邮接收系賊職計算各符元 ΐ 值=第一組符元的延遲相關函數 參值的電路由延遲相關函數設定至少 值’包括使關斷取實部值或虛部值的電路，判 ，出利用延遲相關函數的實部值與虛部值，妓參數值 ❿ ^並利用所制的實部值或虛部值來判_性，設定參 數值二。 〆 摩用擷取下一組符元，計算延遲相關函數之後， 二用上遠，數值一.判斷此時採用實部值還是虛部值，並得 出極性，接著由比較極㈣電路比對參數值二*上述實部 =虛部值的極性’由_極性計數的電路_性是 ，付合所應用的傳輸祕的極性特性，並計算連續符合的 較門播值的電路進行比對與判斷程序，以找 :::„的起始點位置，使在頻率偏移高或著頻率 偏移接近零時仍然可以保有估測效能。 而本發明所揭露的適應性符元起始點計算方法步驟包 後，計算訊號中各組符元的延遲相關函數 之貝部值與虛部值，由絕對值大小作為系統參數值一的設 接著㈣選定的實部钱是虛部值巾简該函數的極 定參數值二。之後擷取下-組符元，㈣相 f函數’根據上述祕參數值-取出相對的實部值或虛部 值’並判斷極性’透過前-組符it所設定的泉數值二比較 目前的符元_延遲相關函數的極性，將比較後的結果繼 9 201008209 續判斷是否符合所應用的傳輸系統的極性特性，透過連、續 極性判斷’再經計數器累計次數達到一設定的門檻值時， 表示得到前置符元的位置，並藉以估測特定符元的起始位 置。 ° 【實施方式】201008209 IX. Description of the invention: [Technical field of the invention] The present invention is an adaptive symbol starting method, in particular, a delay phase contrast device that passes through the operator A and a computing side transmit a polarity alignment, which can be shifted in frequency. Value indefinite parameter value, the starting point of the element. ^Under the estimable signal symbol [Prior Art] OFDM (Orthogonal Frequency Division Multiplexing) system is a (Multi-earner System), its synchronization problem will be more important than single carrier' so any digital communication system The middle synchronization is an indispensable operation = and if there is no shooting step, the signal is transmitted without any connection. There are many conventional synchronization methods, such as the use of training sequences (medium (four) sequence), the way to protect the area (Guard_jntervai_Based, such as US Patent No. 6928048) or the use of pilot signals (10) nal nal). In a packet-switching communication system, data is transmitted in units of packets. When transmitting, especially when receiving a packet, synchronization of code frame and frequency transmission is required to detect Is there a packet coming in? At this point, a frame synchronization circuit is needed to find the starting position of a specific symbol so that the system can process the signal. If the communication system needs to find the packet transmission, the channel identifier is used to estimate the channel. The position of the element, which is the starting position of the symbol used to estimate the channel. In the demodulation process, the receiver 6 201008209 (receiver) in the above packet transmission system starts to receive data at any point in the time domain, such as a communication system using OFDM technology, wherein the modulation is based on the symbol (symb^j), so the first action of the receiver is to detect the start bit of the symbol. (start P〇sition), otherwise it will cause two or two characters due to the error of the starting position of the symbol. The confusion between the meta-symbols causes the symbol to be misjudged, and synchronization is performed at this time. In the data received by the receiver, a preamble is provided, and the towel includes repetitive channel symbols (such as a sturdy symbol). The preamble symbol is mainly used to identify the 〇fdm system. The starting position, and used for channel estimation (channelestimati〇n), please refer to the circuit diagram of the OTDM system receiver in the second figure. . When the OFDM signal is input to the receiver, the analog digital conversion = (ADC) 11 converts the analog signal into a digital signal, and uses a symbol start point detector (symb〇lstartdetect〇r) 15 debt conversion The starting point in the digital signal, and then the FFTfn controller 17 generates a fast Fourier transform (FFT) window of the symbol from the above starting point position • !? δ ί1 ' and then according to the 1 ^ window control signal, after The analog-to-digital converter 11 converts the shouting on the fast-moving Fourier transform 13 . In this example, the analog-to-digital converter 11 converts the received signal into a digit ' and detects the position of each symbol by the symbol start point detector 15, • FF^f, in the received sequence packet The starting position of the header, the information_, the processor I? provides the starting position of the fast Fourier transform 13 to correctly perform the synchronization and the Fourier transform of each signal. Figure: Referring to the signal structure of the general 0FDM system shown in the second figure, the signal received by the receiver is shown as the structure in the figure, if there is no signal structure of the 7 201008209 f area network (WPAN), which includes at least Yes, the symbol % part (Preamble) 21, such as the numbers 1 to 24, and the header 23 and the data part 25. The signal structure of various communication systems has special specifications (speciflcati〇n). The conventional technology is applied to the signal architecture of a specific communication system for analysis to obtain pre-symbols in each signal for accurate channel estimation. Processing with related signals. _ f For example, 'Before the receiver outputs meaningful data, it must be processed by different different mechanisms. For example, it can be matched by means of matching j.) 'Using the signal form conforming to the specific specification and receiving the signal Repeated alignments provide pre-positions within a certain threshold. After deconstructing the pre-symbol, the starting position of the header, such as the position of the label 201, can be accurately obtained, that is, the position of the entire signal is obtained, and the channel estimation can be performed by the receiver. [Summary of the Invention] = The technique and calculation method for finding the pre-symbol in the line code frame synchronization, the method of calculating the device TL can be performed at the frequency offset 2 = pay: ° starting point, and the present invention can be omitted or taken The proposed adaptation::::,. The communication system used for transmission of various packets, by means of the circuit of setting the multi-scale value, so that the performance of the code frame synchronization is not easily affected by the frequency offset. The secret embodiment of the lungs is the thief's job to calculate the symbol ΐ value = the first group of symbols of the delay correlation function parameter is set by the delay correlation function at least the value 'including the turn off the real part value or imaginary part The value of the circuit, judged, using the real and imaginary values of the delay correlation function, 妓 parameter value ❿ ^ and using the real or imaginary part of the system to determine the _ property, set the parameter value two. Try to use the next set of symbols to calculate the delay correlation function, the second use is far, the value is 1. Determine whether the real part value or the imaginary part value is used at this time, and the polarity is obtained, and then the comparison pole (four) circuit is compared. The parameter value two * the above real part = the polarity of the imaginary part value' is calculated by the circuit of the _ polarity _ sex, the polar characteristic of the transmission secret applied, and the circuit that calculates the continuous matching of the gated value is compared and The program is judged to find the starting point position of :::: so that the estimated performance can still be maintained when the frequency offset is high or the frequency offset is close to zero. However, the adaptive symbol starting point calculation disclosed in the present invention is calculated. After the method step package, the shell value and the imaginary part value of the delay correlation function of each group of symbols in the signal are calculated, and the absolute value is set as the system parameter value one. (4) The selected real money is the imaginary value. The final parameter value of the function is two. After that, the lower-group symbol is extracted, and the (four) phase f function 'according to the above-mentioned secret parameter value-takes the relative real part value or the imaginary part value' and judges the polarity 'through the pre-group symbol it The set spring value 2 is compared with the current symbol _ delay correlation The polarity of the function, the result of the comparison will continue to be judged according to the polarity characteristics of the applied transmission system after 9 201008209, and the preamble is obtained by judging the continuous and polarity determinations, and then reaching the threshold value by the cumulative number of counters. The position of the element, and by which to estimate the starting position of the specific symbol. ° [Embodiment]
本發明提供一種適應性符元起始點計算裝置與方法， 其較佳實施例係應用於一封包式傳輸的系統 (packet-switching comnmnication system)中的碼框同 步電路，如無線個人區域網路（WPAN)，利用此碼框同步 電路找出特定符元的起始位置，以便系統作訊號處理，其 中常見的方式有兩種，皆係利用前置符元（preambie symbol^間的相關性找出精確的訊號起始點，係於收到符 元後計算其延遲相關（delay correlation)函數，藉比對出 前置符it後得到通道估計（CE)符元的初始點位^。 根據上述内容，第-種完整符元的計算電路如第三圖 所示，其巾包括接收訊號並處理的計算延遲相關函數的 路30卜取出實部值的電路3〇3、比較極性的電路奶盘比 較Π檻值的電路307等，上述各電路順序地電性，，並 且其連接關係亦顯示此例之執行手段。 〃 弟 -不疋由計昇延遲相關函數的電路301接收通 訊系統的訊號，並計算各符柄延遲㈣函數，接 取出貫部值的祕烟取出延遲相關函數的實部值 part) ’透過所计异各符元或各波形訊號的 實部值後，由比較極性的電路挪判斷各符元的 10 201008209 值，並與上述實部值比較，判斷各符元極性是否符合特定 通訊系、统的規格（設定為預設值），此特定系統的預設值是 指特定通訊系統的前置符元有特定的規格，透過比較運算 . 比對各接收訊號符元的實部值與預設值的極性，若符合預 設值，則啟動一計數器（counter)累計次數；反之，若與 預設值不符’則將計數器歸零。之後，由比較門播值的電 路3〇7判斷上述累計的計數值是否達到一設定的門禮值， 若計數器的值達到此門檻值，即表示得到前置符元，並能 ❹ 藉以估測到此特定系統的通道估計符元的起始位置。 另有第二種電路，如第四圖所示之完整符元的計算電 路示意圖，其中主要包括有接收訊號並計算延遲相關函數 的電路4 01、相位值作為參考值的電路4 〇 3、取出相位值的 電路405、比較相位值與參考值的電路4〇7、根據極性計數 的電路409與比較門檻值的電路411等，各電路依序電性 相連接，並且此順序同時反映出接收訊號、計算前置符元 位置的手段。 鲁與第一種電路不同的是，第四圖所示之電路主要是透 過計算各訊號符元的延遲相關函數取出相位值，而能透過 相位值的比對得到特定通訊系統的通道估計符元位置。 此第二種電路係於接受訊號後’由計算延遲相關函數 的電路401取出各訊號符元的相位值，並接著由相位值作 為參考值的電路403將經時間延遲的第一組擷取到的符元 的延遲相關函數相位作為參考值，此第一組的符元並不會 進行極性判斷’而是將之後所擷取的符元經計算出延遲相 關函數後’利用取出相位值的電路405得出各符元的相位 11 201008209 值後’利用比較相位值與參考值的電路4〇 i信t比對經延遲相關函數得出各符元的相位值與上述參 值作=性’並且其後的延遲相關函數相位值皆與此參考 佶的2對各相位值與—符合特定通訊錢的規格的預設 的電路4G’9H合職侧啟辑數器，由根據極性計數 目；反之則將計果進行計數，累計符合的數 判斷钟F零，最後透過比較門檀值的電路411 ;==點即—的位置，並估= 點計兩種電路’本發明所揭露的適應性符元起始 率偏蒋佶接、Γ的在於設計—種不輕易受頻率偏移高、頻 路，;IfM近零以及頻率偏移值不穩定影響的碼框同步電 部值實㈤㈣虛（麵啊㈣ 鬌 習知社父 比例關係加入一控制電路，即可將 頻率偏缺點都予以克服，使估測效能不會輕易受到 偏移影響而降低估測效能。 所示了般受到頻率偏移影響的輸人訊號&，如方程式⑴ X. =r 移值歲始^影響的訊號’f△與Ts分別為頻率偏 -遲相=示==頻率偏移值固定，計算其 12 201008209 L~\The present invention provides an adaptive symbol starting point computing device and method. The preferred embodiment is applied to a code frame synchronization circuit in a packet-switching comnmnication system, such as a wireless personal area network. (WPAN), using this code frame synchronization circuit to find the starting position of a specific symbol, so that the system can perform signal processing. There are two common ways, which are to use the pre-symbol (preambie symbol^ correlation) The exact starting point of the signal is calculated by the delay correlation function after the symbol is received, and the initial point of the channel estimation (CE) symbol is obtained by comparing the preamble to it. The content, the calculation circuit of the first complete symbol is as shown in the third figure, and the towel includes a circuit 30 for receiving the signal and processing the delay correlation function, a circuit for extracting the real value, and a circuit for comparing the polarity of the circuit. Comparing the devaluating circuit 307 and the like, the above-mentioned circuits are sequentially electrically, and the connection relationship thereof also shows the execution means of this example. 〃 - - 电路 电路 电路 电路 电路 电路 电路 电路 电路 电路 电路 电路The signal of the system, and calculate the delay of each handle (four) function, take out the real value of the secret value of the secret smoke of the cross-section value.)) After passing through the measured real values of the different symbols or waveform signals, The more polar circuit determines the value of 10 201008209 of each symbol, and compares with the above real part value to determine whether the polarity of each symbol meets the specifications of a specific communication system (set to a preset value), the preset of this particular system The value means that the pre-symbol of a specific communication system has a specific specification, and the comparison operation is performed. Comparing the real value of each received signal symbol with the polarity of the preset value, if a preset value is met, a counter is started (counter The cumulative number of times; conversely, if it does not match the preset value, the counter is reset to zero. Then, it is judged by the circuit 3〇7 comparing the homing value whether the accumulated count value reaches a set threshold value. If the value of the counter reaches the threshold value, the pre-symbol is obtained, and the estimated value can be estimated. The channel to this particular system estimates the starting position of the symbol. There is another second circuit, such as the calculation circuit diagram of the complete symbol shown in the fourth figure, which mainly includes a circuit 4 01 for receiving a signal and calculating a delay correlation function, a circuit 4 相位3 for taking a phase value as a reference value, and taking out The circuit 405 of the phase value, the circuit 4〇7 for comparing the phase value with the reference value, the circuit 409 according to the polarity count, the circuit 411 for comparing the threshold value, and the like, the circuits are sequentially electrically connected, and the sequence simultaneously reflects the received signal. The means of calculating the position of the preposition symbol. Lu is different from the first circuit. The circuit shown in the fourth figure mainly extracts the phase value by calculating the delay correlation function of each signal symbol, and can obtain the channel estimation symbol of the specific communication system through the comparison of the phase values. position. The second circuit is to take the phase value of each signal symbol by the circuit 401 for calculating the delay correlation function after receiving the signal, and then the circuit 403 whose phase value is used as the reference value extracts the first group of the time delay to The phase of the delay-correlation function of the symbol is used as the reference value, and the symbols of the first group do not perform the polarity judgment, but the circuit that takes the phase value after calculating the delay correlation function 405, the phase 11 of each symbol is obtained, and the value of the phase value of the symbol is compared with the reference value. The phase correlation value of each symbol is obtained by comparing the phase value of the phase value with the reference value with the above parameter. The subsequent phase values of the delay correlation function are the same as the two pairs of phase values of the reference 与 and the preset circuit 4G'9H of the specific communication money, according to the number of polarities; Then count the count, count the number of coincidences to determine the clock F zero, and finally pass the position of the circuit 411 that compares the gate value; == point is the position, and estimate the two circuits' the adaptability of the invention. Symbol starting rate佶 Γ Γ 在于 在于 在于 在于 设计 设计 设计 设计 If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If If By adding a control circuit to the parent proportional relationship, the frequency offset can be overcome, so that the estimated performance is not easily affected by the offset and the estimated performance is reduced. The input signal & , as in equation (1) X. = r shift value of the beginning of the ^ affected signal 'f △ and Ts respectively frequency offset - late phase = indication = = frequency offset value fixed, calculate its 12 201008209 L~\
Yz=HXn^Xn+D^r «=0 7ί=〇 1-1 §(r x^·2^) x(rn+DXej^D)TsYz=HXn^Xn+D^r «=0 7ί=〇 1-1 §(r x^·2^) x(rn+DXej^D)Ts
Hr:乂 UdW2 知 Ts x eJWA(n+D)Ts e ^ΣΚ!2 (2) ..™ i rf r ^w 木 X到頻率偏移f△的影響， *頻率偏移值愈大’騎遲_函數的相位愈大；頻 t值接近零時’脑遲相關函數的相 單 乍判斷’在頻率偏移偏高時實部值易::;屯 • i= T使估測誤判；同樣地，若單純地只取二 負二竟變ί頻ί偏移接近二零時相位值容易受雜訊影響正 :效能不輕易受到頻率偏移=讓 鄰近的=符元，作為參考判斷的延遲相關函數更使用最 =延遲相關函數相位作為參考值的方式， ^移不穩定時，用來設定系統參數值 其後的延遲相關函數差異太大導致誤判，= 13 201008209 前置符元位置。 上述第一種電路是建立右 不易變化下，因此甚4 遲相關函數的實部值極性 =議高時常常會有婁:值 ^數的貫部值並非是—固定極性的值，估丄= 而第二種電路則是建立力: 不易變化下，類似地，若是取關函數的相位值極性 斷，雖然在頻率偏移值偏高時仍可使用，但在 j ;Γ:、Π會有相位太小易受雜訊影響，導致相位極“ 不穩定時，常常會使參考值誤判，估測效能降I里 斤故本發明則再提出如第五圖所示之適應 2裝置，其電路方塊顯示本發明應用以實現特定通二 步電路，各電路顯示執行各程序料段。盆中' 參 接收純訊號的計算延遲相關函數的電路則， 6十，接收到的各組符元的延遲相關 實部值或虛部值的電路503、比七魅ΑΑ/接者有判斷取 性計數的電路50技比較門Λ 2 、根據極 :電性連接的電路同時表達得出前置符元 二除了作，計算延遲相關函數結果的:：： 主要疋有一设定簽數值的電路513，能由 極性設定至少兩個參數值作為比較之 後各·、'且付π的依據。此實施例可省去儲存完整符元的記憶 14 201008209 =:=頻率偏移高或者頻率偏移接近零時仍 詳=地說，當計算延遲㈣函數的電路π 時’計算該組符元的延遲相關函數，並透過:二 實部值或虛部值的電路503判斷 j圳斷取 值，在-較佳實施射 &中纟貫。卩值與虛部 實部值或是虛部值。:有絕對值判斷所採用為 電㈣的延：路算延遲相關_ ❿ 組符元（或說前一且符丄1儲存計算第— / 、，，付7L)的延遲相關函數的結果。 間後之:取相電路501延遲某-段時 性遠接延沪Φ 亚汁异其延遲相關函數，再由電 #7L 5η的設定參數值的電路513根據前一組 相對於之後接收的符元為前-組符元， 失數值、鱼-Γ延遲相關函數’設定至少兩個參數值，如 數值二，其中參數值-為利用前-組符元的 由實部曰戶斷的實部值或是虛部值，而參數值二為 性。σ 5疋虛部值所觸各組符元的延遲相關函數的極 寸所：上述實部值或虛部值的電路 503先得出出目 元）的过遽*組付兀（相對於前一組符元，此為後一組符 數值㈣1關聽的實部與虛部，並麟之前由設定參 關函數的實部值或是數值―，判斷採用目前延遲相 或虛^的路奶除了得知由判斷取實部值 戶斤判斷出採用的實部值或是虛部值之 201008209 外，由其電性連接的設^參數值的電路5丨3得到來數值 所4達的極，，如前述内容，此參數值二 函數判斷極n I ’與目麵接收的符元組的延遲相關 % . A/.,，比較極性的電路505即比較參數值二盥由 的實部值或是虛部值之極性差異，並： ^ Η目5的極性。其—實闕係透過共輛相乘的手段 判斷疋否極性相符。Hr:乂UdW2 know Ts x eJWA(n+D)Ts e ^ΣΚ!2 (2) ..TM i rf r ^w Wood X to frequency offset f△, *The larger the frequency offset value The phase of the late _ function is larger; when the frequency t value is close to zero, the phase single 乍 judgment of the brain late correlation function is easy when the frequency offset is too high::; 屯• i= T makes the estimation misjudge; Ground, if only take two negatives and two actually change ί frequency ί offset close to the 20th phase value is susceptible to noise impact: performance is not easily affected by frequency offset = let the adjacent = symbol, as a reference delay The correlation function uses the most = delay correlation function phase as the reference value. When the ^ shift is unstable, the difference between the delay correlation function used to set the system parameter value is too large, resulting in a false positive, = 13 201008209 pre-symbol position. The first circuit mentioned above is to establish the right is not easy to change, so the polarity of the real part of the 4th late correlation function = there is often a 议: the value of the value of the value is not the value of the fixed polarity, estimated 丄 = The second circuit is to establish the force: not easy to change, similarly, if the phase value of the function of the off function is off, although it can be used when the frequency offset value is high, but in j; Γ:, Π The phase is too small to be affected by noise, which causes the phase to be extremely unstable. The reference value is often misjudged, and the estimated performance is reduced. Therefore, the present invention proposes an adaptation 2 device as shown in the fifth figure. The block shows the application of the present invention to implement a specific two-step circuit, each circuit displays the execution of each program segment. The circuit in the basin receives the calculation of the delay correlation function of the pure signal, and then the delay of each received symbol. The circuit 503 of the relevant real part value or the imaginary part value is compared with the circuit 50 of the seven-character/receiver having the judgment probability count. 2, according to the pole: the electrically connected circuit simultaneously expresses the pre-symbol 2 Except for the calculation, the result of the delay correlation function is ::: Mainly, there is a circuit 513 for setting the value of the sign, and at least two parameter values can be set by the polarity as the basis of each of the comparisons, and the π is added. This embodiment can save the memory of storing the complete symbols. 14 201008209 =:= When the frequency offset is high or the frequency offset is close to zero, it is still detailed. When calculating the circuit π of the delay (four) function, the delay correlation function of the group of symbols is calculated, and the circuit of the two real part values or the imaginary part value is transmitted. 503 judges the j Shenzhen break value, in the preferred implementation of the shot & 卩 与 and imaginary real value or imaginary part value.: There is absolute value judgment used as electric (four) delay: way calculation delay Correlation _ ❿ The result of the delay correlation function of the group symbol (or the previous one and the storage number 1 - /,,, pay 7L). After the phase: the phase taking circuit 501 delays a certain period of time delay The Shanghai Φ juice is different from the delay correlation function, and the circuit 513 for setting the parameter value of the electric #7L 5η is based on the former group with respect to the symbols received afterwards as the pre-group symbol, the missing value, the fish-Γ delay correlation function. 'Set at least two parameter values, such as the value two, where the parameter value - is the pre-group symbol The real or imaginary value of the real part of the household, and the parameter value is two. σ 5 疋 imaginary part of the delay correlation function of each group of symbols: the above real value or virtual The circuit 503 of the partial value first obtains the 遽* group 兀 of the 目* (relative to the previous group of symbols, this is the real and imaginary part of the latter group of values (4) 1 and the imaginary part of the quotation The real value or the value of the off function is used to judge whether the current delay phase or the virtual ^ road milk is used to determine the real or imaginary value of the 201008209, which is judged by the actual value of the real part. The circuit 5丨3 of the electrically connected parameter value obtains the pole of the value 4, and as the foregoing, the parameter value two function judges the pole n I '% related to the delay of the symbol group received by the mesh A/.,, the circuit of the polarity 505 compares the difference between the real value of the parameter value and the polarity of the imaginary part, and: ^ The polarity of the item 5. The 阙 阙 透过 透过 透过 共 共 共 共 共 共 共 共 共 共 共 共 共 共
接著’經極性比對後，將結果傳遞至根據極性計數的 電路5〇7’、__μ符合目祕應關軌系統的極 性，由根據極性計數的電路5们騎計數，即透過計數器 累計連續具有與目_助的通訊系統相同極性的次數。σ 其中’若經判斷的極性與目前所應用的通訊純的極性特 性相同’則啟動計數H累加次數；反之，若判斷的極性不 符則將D十數益歸零，並通知系統重新擷取訊號與計算延 遲相關函數等程序。最後，則利用比較門檻值的電路509 根據計數㈣輸岐來與―服值比較，撕是否達到此 予^的Η檻值’若計數H的值達到此門檻值，表示得到連 績相付的極性’也絲估測此通訊系統的前置符元中用以 通道估汁的付元初始點位置，若並未達到此門播值，則需 再偵測計數器的值。 第六圖顯示透過延遲相關函數判斷符元極性的示意 圖，此例為封包式傳輪的通訊系統（packet_switching communication system )的封包格式，至少包括有前置符元 60(包含通道估計符元61)、標頭（header) 63與資料65 等主要的部分。此例中’前置符元包括有24個用於判斷極 16 201008209 „相互的關聯性具有特定極 道估计符元61，此例有6個。 w 1括複數個通 舉例來說，在最後複數個 之間具有特定關勝置2元（標號 =的極性’將符元區分為複數組，此例’為^出此前置 唬22的符元形成—組符元(標示：二號19與標 ，元形成另一組符元（標示602)，^f 2〇與標號U 符凡形成-纽符元（標示6〇3)，利用^^與標號24的 生各組符元的延遲相關函數。 ^程式（2)產 極性關係即為標示6〇1所表示嗲 _ 數兩兩相乘後得出Αι、標示 表示的：遲相關函 函數相乘後得出A2、標示6〇3所表示：：付，遲相關 數兩兩相乘後得出a3，極性判斷結果為7°的，遲相， 過連續極性的比對得出此前置符位1 = 3。接者透 標頭位置，進心準確解 七圖行的適應性符元起始點計算方法如第 曰所不之主要k程，由於本發明實現竭框同 利用兩兩延遲相關函數間的極性作為判斷 =位置的依據’並可估測出特定符元的起始點，在此較 ’首先如步驟S701所示’先接收由特定通訊 糸統的訊號’如前述的封包式傳輸的通訊系、統， =包為^位傳送’故接收的訊號為包括一組完整符元的 、匕，接著由計算延遲相關函數的電路計算 的延遲相關函數（步驟S703)。 賊的付兀 接著設定系統參數值。在一較佳實施例中，由前一組 17 201008209 =巧遲_函_斷採时部 定參數值一，作二對值大小來判斷，依此結果設 =以此所 曰 1的該延遲相關函數的極性，設定參數值二。 η士χί由所接收的第一組符元來計算延遲相關函數，且此 Τ乍極性的判斷，只比較其實部值與 ❹ 統r…定，而延遲相關函數 %式（2)，其結果以實部值與虛部值表示。 上述擷取的封包來看’並非僅取出第—組符元，而 ::二遲後’娜前一組符元的延遲相關函數的相 極性的判斷，以降低錯誤判斷的可來f : 下來ί的Γ組同樣將計算其延遲相關函數，以判斷接 並所採用延遲相關函數之實部值或虛部值， 根據參數值二觸目前符元^輯相關函數的極性。 延設定參數值一的實施例中，而若第一組的符元的 關函數實部值的絕對值大於虛部值的絕對值，則取 k遲相關函數實部值設定參數值一，並用以盥 =付7C組的，元的延遲相關函數實部值作為極性比較的 值#’若第一組的符元的延遲相關函數實部值絕對 :虛视絕對值，則取出虛部值作為_，以此設 =^之後’由採用的實部值或虛部值的極性設定表 要文值一（步驟S705)。 " 18 201008209 經過上述系統參數值的設定之後，+ 符元組的極性是否與上述參數值 ^斷目前所擷 ^所表賴極性舆由目輯接收的符元組中判斷採用的 貫$值或虛部值的極性，依照特定系統 沾 =_ΓΓ爾元的極性是否與該系二= f相冋，右相同，則啟動計數器進行累計Then, after the polarity comparison, the result is transmitted to the circuit 5〇7' according to the polarity count, __μ conforms to the polarity of the tracking system, and is counted by the circuit 5 according to the polarity count, that is, the cumulative counter has cumulatively The number of times the same polarity as the communication system of the target. σ where 'if the determined polarity is the same as the currently used communication pure polarity characteristic', then the count H is counted up; otherwise, if the determined polarity does not match, the D-number is returned to zero and the system is notified to retrieve the signal. Programs such as calculating delay related functions. Finally, the circuit 509 for comparing the threshold value is compared with the service value according to the count (four) input, and whether the tear value reaches the threshold value of the ^ is obtained. If the value of the count H reaches the threshold value, it indicates that the value of the balance is paid. The polarity 'is also estimated the initial position of the pay element used for channel estimation in the pre-symbol of the communication system. If the gate value is not reached, the counter value needs to be detected again. The sixth figure shows a schematic diagram for determining the polarity of a symbol through a delay correlation function. This example is a packet format of a packet_switching communication system, and includes at least a preamble 60 (including a channel estimation symbol 61). Main parts such as header 63 and data 65. In this example, the 'preposition symbol includes 24 for judging pole 16 201008209 „ mutual correlation has a specific pole estimation symbol 61, and this example has 6. w 1 includes plural numbers, for example, at the last plural There is a specific Guan Sheng set 2 yuan between the two (the polarity of the label = the symbol is divided into a complex array, this example is the symbol formed by the previous set of 22 - group symbol (mark: 2 19 and The mark, the element forms another set of symbols (marker 602), and the ^f 2〇 and the mark U form the - sign element (labeled 6〇3), using the delay correlation of the ^^ and the sign of the group of symbols Function. ^ Program (2) The polarity relationship is indicated by the mark 6〇1. The number is multiplied by two and two, and the result is Αι, and the mark is indicated: the late correlation function is multiplied to get A2 and mark 6〇3. Representation:: Pay, the late correlation number is multiplied by two and two to get a3, the polarity judgment result is 7°, the late phase, the comparison of the continuous polarity gives the preamble bit 1 = 3. Position, the heart accurately solves the seven-character line of the adaptive symbol starting point calculation method, such as the main k-way of the third, because the present invention achieves the same frame with the use of two The polarity between the delay correlation functions is used as the basis of the judgment=position' and the starting point of the specific symbol can be estimated. Here, 'firstly, as shown in step S701, 'the signal received by the specific communication system' is received as described above. The communication system of the packet transmission, the system = the packet is transmitted, so the received signal is a delay correlation function calculated by a circuit that calculates a delay correlation function, including a complete set of symbols (step S703). And then set the system parameter value. In a preferred embodiment, the previous set of 17 201008209 = coincidence_letter_breaking time part of the parameter value is determined by two pairs of values, according to the result = Set the parameter value two according to the polarity of the delay correlation function of 曰1. η士χί calculates the delay correlation function from the first group of symbols received, and the judgment of the polarity is only compared with the actual value. And the system is fixed, and the delay correlation function is %(2), and the result is expressed by the real part value and the imaginary part value. The above-mentioned captured packet looks like 'not only the first-group symbol, but:: two Delayed related letter of the former group of symbols The phase polarity is judged to reduce the error judgment. f: The ί group will also calculate its delay correlation function to determine the real or imaginary value of the delay correlation function used in the conjunction, according to the parameter value two. Touch the current polarity of the correlation function of the symbol. In the embodiment of setting the parameter value one, if the absolute value of the real value of the function of the first group is greater than the absolute value of the imaginary value, then k is delayed. The real value of the correlation function sets the parameter value one, and is used to 盥=pay the 7C group, the real value of the delay correlation function of the element as the value of the polarity comparison #' If the real value of the delay correlation function of the first group of symbols is absolute: If the absolute value is imaginary, the imaginary part value is taken as _, and the value of the table attribute value is set by the polarity of the real part value or the imaginary part value used (step S705). " 18 201008209 After the above system parameter value is set, whether the polarity of the + symbol group and the above parameter value are broken, the current polarity is determined by the polarity of the symbol group, and the value of the symbol value received by the mesh is determined. Or the polarity of the imaginary part value, according to whether the polarity of the specific system ==_ΓΓ尔元 is the same as the system 2 = f, the right is the same, then the counter is started to accumulate
值時，繼續操取下一組符元，計算= it Ϊ符元設定的她值—靖採㈣實部值 5皿邛值，透過别一組符元設定的參數值二判斷極性等步 反之則重置（reset)計數器，並返回原擷取符元的步 t同樣再繼續擷取符心計算延遲相_數、設定系統 二丈值、比較極性等步驟（步驟S707)。如此重覆上述步 戈累D十該極性與傳輸系統前置符元之極性相同情況 -/> 士 A數，直到計數器的值達到一預設的門檻值，當累計 i ^到此門檻即得出此傳輸系、统的前置符元的位 二表示找到特定符元的起始點位置（步驟S709)。 法第八圖顯示-適應性符元起始點計 算方法的詳細實施 本發明所提供實現碼框同步電路的方法包括先 %二异延遲相關函數的電路明包為單元接收系統訊 ^姻封Ϊ包括該系統的—個完整的符元（步驟S8G1)，接 :二：符元J步驟S8〇3)，再利用計算延遲相關函數的電 μ — #各1且符元的延遲相關函數（步驟S805)。所擷取的 皆元匕括第組符元，與之後的符元組，透過延遲電路儲 19 201008209 存所擷取的前一組符元的延遲相關函數（第一組符元經過 時間延遲，相對成為前一組符元）。 接著進行設定系統參數值，此例中包括參數值一與參 數值一（步驟S807)，若前一組符元為第一組符元，則計 算出來的延遲相關函數並不作極性的判斷，而是只比較函 數中的貫部值與虛部值的絕對值大小（參考方程式（2))， 設定參數值一，並以該值所表示的極性設定參數值二。而 後一組符元則應用參數值一設定採用的實部值或虛部值，When the value is, continue to fetch the next set of symbols, calculate = her value set by the symbol - Jing Cai (four) real value of 5 values, determine the polarity by the parameter value set by another set of symbols, etc. Then, the counter is reset and returned to the step t of the original symbol. Similarly, the steps of calculating the delay phase_number, setting the system binary value, comparing the polarity, and the like are continued (step S707). Repeating the above steps, the polarity of the step is the same as the polarity of the pre-symbol of the transmission system -/> the number of A, until the value of the counter reaches a preset threshold, when the cumulative i ^ reaches this threshold It is concluded that bit 2 of the preamble of the transmission system indicates that the starting point position of the specific symbol is found (step S709). The eighth embodiment shows a detailed implementation of the method for calculating the starting point of the adaptive symbol. The method for implementing the code frame synchronization circuit of the present invention includes the circuit clearing of the first two different delay correlation function for the unit receiving system. Including the complete symbol of the system (step S8G1), followed by: 2: symbol J step S8 〇 3), and then use the delay μ correlation function of the delay μ (1) and the symbol delay correlation function (step S805). The extracted elements include the first group of symbols, and the subsequent symbol groups, through the delay circuit storage 19 201008209, the delay function of the previous group of symbols (the first group of symbols has a time delay, Relatively become the previous set of symbols). Then, the system parameter value is set. In this example, the parameter value 1 and the parameter value are included (step S807). If the previous group of symbols is the first group of symbols, the calculated delay correlation function is not determined as the polarity. It is to compare only the absolute value of the singular value and the imaginary part value in the function (refer to equation (2)), set the parameter value one, and set the parameter value two with the polarity indicated by the value. The latter set of symbols applies the real value or the imaginary value of the parameter value.
亦設定另一參數值一；並利用採用的實部值或虛部值與之 前設定的參數值二比較，判斷極性。以一較佳實施例為例， 若由此第一組符元的延遲相關函數的實部值的絕對值大於 虛部值的絕對值，則取出實部值設定為參數值一；若實部 值的絕對值小於虛部值的絕對值，則取出虛部值設定參數 值 而極性即為此使用的實部值或虛部值的正負值而設 定參數值二。 ，後，依據所採用前一組符元的延遲相關函數的實部 值或疋f部值（參數值決定後一組所採用的值，並以 此與之前奴的參數值二比較，躺由目前符植計算的 延遲相關函數的極性（步驟删9)，比如透過符元的延遲 相關函數的實部值或是虛部值與參數值二相_值來判斷 極f生而極性的詳細判斷可參閱上述第六圖所述之内容。 鑛參數值二的極性判斷，將比較後的結果接著 ㈣二:所應用的傳輸系統的極性特性’也就是該系 、-充的各刚置付7L的極性（步驟S8U) 則啟動計數器累計女數f牛酈性氐和I』I疋） 卞-人數〔步驟S813) ;若極性不同（否）， 20 201008209 則重置（reset)計數器f。 繼續擷取下-組符元/以回到步驟麵， 數、設定參數、判斷極性等步了；^各組付狀延遲相關函 連續211的輪纽，躺經過計數器 ί:=ί 糸統前置符元經延遲相關函數計算 之極性相同fWf的錄是否物—設定的狀值 Φ =:斷t否有連續::Ϊ元的延遲相關函數符:特定系統 前置符元值：定是為了能排除誤差，且準確判斷 續偵測，直到計數器的值=過門檻值⑷，則繼 别- y 大於預設的門檻值（是），表示得 ^置付兀的位置（步驟S817)，並藉以估測 起始點位置（步驟S819)。 的 法 =明所提供之適應性符元起始點計算裝置與計算方 輿其他技術相互比較時，具備下列優點： 1.本發明於使用控制電路（包括延遲電路與設定參數 值的電路）設定系統參數值—與參數值二，作為比 較前置符元極性的依據，於頻率偏移偏高時仍铁可 以保有估測效能； 2·本發明同樣能於頻率偏移接近零時仍然可以保有 估測效能； ' 3.本發明用來作設定的延遲相關函數除了是取自第 一組符元外，更再取自另一鄰近的一組符元，可避 免當頻率偏移收敛不夠快時，用來設定系統參數值 21 201008209 的延遲相關函數與其後的延遲相關函數差異太大 導致誤判的問題。 綜上所述，本發明為一種適應性符元起始點計算裝置 與計算方法，透過一延遲電路與設定參數值的電路擷取不 同時間點的訊號，並設定參數值，以其延遲相關函數進行 極性比對，進而得到符元起始點位置，讓實現碼框同步的 電路能不輕易的受到頻率偏移影響。 惟以上所述僅為本發明之較佳可行實施例，非因此即 侷限本發明之專利範圍，故舉凡運用本發明說明書及圖示 内容所為之等效結構變化，均同理包含於本發明之範圍 内，合予陳明。 【圖式簡單說明】 第一圖所示為習知的OFDM系統接收機的電路方塊 不意圖， 第二圖所示為一般OFDM系統之訊號結構示意圖； 第三圖所示為一種完整符元的計算電路示意圖； 第四圖所示為另一種完整符元的計算電路示意圖； 第五圖所示為本發明適應性符元起始點計算裝置的方 塊不意圖， 第六圖顯示透過延遲相關函數判斷符元極性的示意 圖， 第七圖所示為本發明適應性符元起始點計算方法之流 程圖之一； 22 201008209 第八圖所示為本發明適應性符元起始點計算方法之流 程圖之二。 【主要元件符號說明】 類比數位轉換器11 FFT窗口控制器17 前置符元部份21 資料部分25 接收機10 符元起始點偵測器15 快速傅利葉轉換13 標頭部份23 位置201 計算延遲相關函數的電路301 取出實部值的電路303 比較極性的電路305 比較門檻值的電路307 計算延遲相關函數的電路401 相位值作為參考值的電路403 取出相位值的電路405 比較相位值與參考值的電路407 根據極性計數的電路409 比較門檻值的電路411 計算延遲相關函數的電路501 判斷取實部值或虛部值的電路503 比較極性的電路505 根據極性計數的電路507 比較門檻值的電路509 23 201008209 延遲電路511 設定參數值的電路513 前置符元60 通道估計符元61 標頭63 標示 601, 602, 603 第一個通道估計符元610 資料65Another parameter value is also set; and the polarity is determined by comparing the real or imaginary value used with the previously set parameter value. Taking a preferred embodiment as an example, if the absolute value of the real part value of the delay correlation function of the first group of symbols is greater than the absolute value of the imaginary part value, the real part value is set to be the parameter value one; If the absolute value of the value is less than the absolute value of the imaginary part value, the imaginary part value setting parameter value is taken out and the polarity is the positive or negative value of the real part value or the imaginary part value used for this purpose, and the parameter value 2 is set. After, according to the real value of the delay correlation function of the previous set of symbols or the value of the 疋f part (the value of the parameter determines the value used by the latter group, and compared with the parameter value of the previous slave, At present, the polarity of the delay-correlation function calculated by the plant is calculated (step 9). For example, the real-value or the imaginary value of the delay-correlation function of the symbol or the two-phase value of the parameter value is used to determine the detailed judgment of the polarity and the polarity. Refer to the content described in the sixth figure above. The polarity of the value of the mine parameter is judged, and the result of the comparison is followed by (4) 2: the polarity characteristics of the applied transmission system 'that is, the line of the system, the charge of each charge 7L The polarity (step S8U) starts the counter to accumulate the number of females and the number of I 疋 I 疋 人数 - number of people [step S813); if the polarity is different (no), 20 201008209 resets the counter f. Continue to take the next-group symbol/ to return to the step surface, number, set parameters, determine the polarity, etc.; ^ each group delays the relevant letter continuous 211 of the wheel, lying past the counter ί:=ί The input symbol is calculated by the delay correlation function. The polarity of the same fWf is recorded. The set value Φ =: break t is continuous: the delay related function of the unit: the specific system preamble value: it is for The error can be eliminated, and the continuous detection is accurately determined until the value of the counter = the threshold value (4), and then -y is greater than the preset threshold value (Yes), indicating that the position is set (step S817), and Thereby, the starting point position is estimated (step S819). When the adaptive symbol starting point calculation device provided by the method is compared with other techniques of the computing method, the following advantages are obtained: 1. The present invention is set using a control circuit (including a delay circuit and a circuit for setting a parameter value). The system parameter value—and the parameter value two, as the basis for comparing the polarity of the pre-symbol element, can still maintain the estimated performance when the frequency offset is too high; 2. The invention can also retain the frequency offset when it is close to zero. Estimating performance; '3. The delay correlation function used by the present invention is set to be taken from another group of symbols in addition to the first group of symbols, thereby avoiding that the frequency offset does not converge fast enough. When the delay correlation function used to set the system parameter value 21 201008209 is too different from the delay correlation function, the problem of misjudgment is caused. In summary, the present invention is an adaptive symbol starting point calculation device and a calculation method. A delay circuit and a parameter setting circuit are used to extract signals at different time points, and parameter values are set to delay related functions. Polarity comparison is performed to obtain the starting point position of the symbol, so that the circuit for synchronizing the code frame can be easily affected by the frequency offset. However, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, equivalent structural changes that are made by using the specification and the contents of the present invention are equally included in the present invention. Within the scope, it is combined with Chen Ming. BRIEF DESCRIPTION OF THE DRAWINGS The first figure shows the circuit block of the conventional OFDM system receiver. The second figure shows the signal structure of the general OFDM system. The third figure shows a complete symbol. Schematic diagram of the calculation circuit; the fourth figure shows a schematic diagram of the calculation circuit of another complete symbol; the fifth figure shows the block intention of the adaptive symbol starting point calculation device of the present invention, and the sixth figure shows the transmission delay correlation function. A schematic diagram for determining the polarity of a symbol, and a seventh diagram showing one of the flowcharts for calculating a starting point of an adaptive symbol of the present invention; 22 201008209 The eighth figure shows the calculation method of the starting point of the adaptive symbol of the present invention. Flow chart two. [Main component symbol description] Analog-to-digital converter 11 FFT window controller 17 Pre-signet part 21 Data part 25 Receiver 10 Symbol Start point detector 15 Fast Fourier transform 13 Header part 23 Position 201 Calculation Circuit 301 for delay correlation function Circuit 303 for real value extraction 303 Circuit 307 for comparing polarity 307 Circuit for comparing threshold value Circuit 401 for calculating delay correlation function Circuit 401 for reference value Circuit 405 for taking out phase value 405 Comparing phase value with reference The value circuit 407 calculates the delay correlation function based on the circuit 409 of the polarity count circuit 409. The circuit 501 which determines the real part value or the imaginary value 503 compares the polarity. The circuit 505 compares the threshold value according to the polarity count circuit 507. Circuit 509 23 201008209 Delay Circuit 511 Circuit 513 for Setting Parameter Values Preamble 60 Channel Estimation Symbol 61 Header 63 Indicator 601, 602, 603 First Channel Estimated Symbol 610 Data 65
24twenty four