201214986 六、發明說明： 【發明所屬之技術領域】 本發明係有關用以經由正交分頻多工（OFDM )符號 以傳輸資料的傳輸器，其中資料係提供.自複數不同的資料 • 管線。 ' 本發明之實施例已找出用於接收使用OFDM符號所傳 遞之資料的應用，該些OFDM符號係使用通訊系統來傳輸 ’該些通訊系統包含遍及一地理區域而配置的複數基地站 。於某些實施例中，通訊系統被配置以廣播視頻、音頻或 資料。 【先前技術】 正交分頻多工（OFDM )是一種在通訊系統中被發現 爲極有利的調變技術，諸如（例如）那些設計成依據第一 及第二代數位視頻廣播地面標準（DVB-T/T2 )而操作的 通訊系統；且亦被提議於亦已知爲長期進化（LTE)之第 四代通訊系統。OFDM可被一般性地描述爲提供平行調變 之K窄頻帶副載波（其中κ爲整數），各副載波係傳遞一 經調變的資料符號，諸如正交調幅（QAM )調變符號或四 相移鍵控（QPSK )調變符號。副載波之調變被形成於頻 率領域並轉變爲時間領域以供傳輸。因爲資料符號係平行 地傳遞於副載波上，所以相同的經調變符號可被傳遞於各 副載波上一段延長的週期，其可較無線電頻道之同調時間 更長。副載波被同時地平行調變，以致與經調變載波之結 -5- 201214986 合形成一 OFDM符號。OFDM符號因此包含複數副載波，其 各以一不同的調變符號同時地調變。 於下一代手持式（NGH )電視系統中，已提議使用 OFDM來傳遞電視信號自遍及一地理區域而配置的基地站 。於某些範例中，NGH系統將形成一網路，其中複數基地 站係同時地傳遞OFDM符號於相同的載波頻率上，藉此形 成一所謂的單頻網路。由於OFDM之一些性質，一接收器 可從二或更多不同的基地站接收OFDM符號，該些基地站 可接著被結合於接收器中，以增進所傳遞資料之完整性-雖然單頻網路在操作及所傳遞資料之增進的完整性上 具有優點，但假如需要傳遞地理區域之一部分的本地資料 時其亦帶有一項缺點。例如，眾所周知的在英國，國家載 波（BBC )廣播電視新聞遍及整個國家網路，但接著於某 些時刻切換至「本地新聞」，其中係傳輸特別有關國家網 路內之本地區域的本地新聞節目。然而，英國操作一種多 頻DVB_T系統，以致本地新聞或任何種類的本地內容之插 入均是不重要的，因爲不同區係傳輸DVB-T電視信號於不 同的頻率而因此電視接收器僅調至該區之適當載波頻率而 無來自其他區之干擾。然而，於單頻網路中提供一種配置 以本地化地插入資料係存在一技術問題。 US 2〇〇8/0 159186已揭露了一種已知的技術，用以提 供一階層式或多層調變架構於單頻OFDM網路中。階層式 調變架構係提供複數調變層，其可被用於同時地傳遞資料 自不同的資料源或管線。 -6- 201214986 【發明內容】 依據本發明，提供一種接收器，用以接收並復原來自 正交分頻多工（OFDM)符號之資料符號。該些〇fdm符號 包括形成於頻率領域中並以待傳遞資料符號調變的複數副 載波符號’其中該些資料符號已被接收以供傳輸於來自第 一資料管線、或者該第一資料管線和本地插入管線之 OFDM符號上，及假如該些資料符號已被接收自該第—資 料管線’則該些資料符號係使用第一調變架構而被調變至 該些OFDM符號之該些副載波上；或假如該些資料符號已 被接收自該第一資料管線和該本地插入管線，則該些資料 符號係使用第二調變架構而被調變至該些OFDM符號之該 些副載波上。該接收器包含一調諧器，其被配置以於操作 時檢測一代表該些OFDM符號之無線電頻率信號並形成— 代表該些OFDM符號之基頻信號，一OFDM檢測器，其被配 置以於操作時復原來自該些基頻OFDM符號之該些副載波 的調變符號，及一解調器。該解調器被配置以於操作時 接收該些調變符號，及 根據一控制信號’在第一輸出上從該些調變符號產生 該第一資料管線之資料符號的輸出串，或者在該第一輸出 上從該些調變符號產生該第一資料管線之資料符號的該輸 出串並在第二輸出上產生該本地插入管線之資料符號的輸 出串，其中該第一調變架構爲低階調變架構，其提供來自 複數平面中較該第二調變架構（其爲高階調變架構）更少 201214986 的群集點數之値給第一調變符號，該第二調變架構提供其 被配置在該複數平面中與該第一調變架構之相應値有關的 値給第二調變符號，其效果爲：該第二調變架構的該些第 二調變符號之一的檢測將提供來自該本地插入管線及/或 該第一資料管線之資料符號，並容許檢測來自該第一調變 架構（其提供來自該第一資料管線之資料符號）之第一調 變符號’於存在來自該第二調變架構之調變符號時，藉此 提供複數調變層給該調變器。 再者，該解調器被配置以於操作時 藉由識別依據該第一調變架構之群集點並產生相應於 該識別之群集點的該第一資料管線之該些資料符號，以產 生該第一資料管線之該些資料符號，及/或 藉由識別依據該第二調變架構之群集點並產生相應於 該識別之群集點的該第一資料管線和該本地插入管線之資 料符號’以產生該第一資料管線和該本地插入管線之該些 資料符號。該控制信號對該解調器指示其來自該本地插入 管線之該些資料符號已被傳輸於該些接收的OFDM符號中 依據US 2008/0159186 (公告於2008年7月3曰）中所 揭露之配置，單一載波頻率OFDM網路設有一種設施，用 以藉由使用兩相關調變架構而同時地從不同管線傳遞資料 來形成複數不同的調變「層」。如稍後將解釋，選擇第一 調變架構以從第一資料管線傳遞資料，及選擇與該第一調 變架構相關的第二調變架構以依據該第一和第二通訊管線 * 8 - 201214986 來傳遞資料。第一調變架構包含在複數平面中與該第—調 變架構相較下增加的群集點數。 依據本發明之範例實施例，配置一種接收器，用以接 收來自第一資料管線'或者該第一資料管線和本地資料管 線之資料符號。該接收器因此被配置以檢測並復原來自由 一通訊系統所傳遞之OFDM符號的資料，該通訊系統被配 置以致來自其形成一通訊網路之複數基地站的—或更多基 地站被選擇以經由其具有依據該第二調變架構而被調變之 副載波的OFDM符號來傳輸本地內容。因此，該第二調變 架構被用以傳達來自該第一資料管線和該本地插入管線之 資料符號。由於該第二調變架構相對於該第一調變架構之 配置，即使當傳輸於相同無線電載波上時來自該第一資料 管線之該些資料符號仍可被接收，因爲來自該第一調變架 構之群集點的檢測將需要較該第二調變架構更低的信號雜 訊比。這是因爲該第一調變架構形成群集點之次集合於該 第二調變架構之該複數平面上，其可被視爲該第二調變架 構之更粗略的版本，以致複數平面中介於第一調變符號的 群集點間之差異容許來自第一資料管線之資料被更輕易地 復原。再者，因爲其他基地站可能不是在傳遞本地服務插 入管線資料，所以接收器（於其中配置有這些其他基地站 之地理區域中）仍將能夠檢測來自第一資料管線之資料。 此係因爲：針對一依據第一調變架構而檢測OFDM符號的 檢測器而言，使用第二調變架構而於共同無線電頻率載波 上傳輸自一相鄰基地站的OFDM信號將僅呈現爲雜訊。因 201214986 此，提供一種在單頻網路中插入本地內容之有效且效率高 的方法。 於某些範例中，接收器可被配置以接收OFDM符號， 其係於某些分時多工框中，使用第二調變架構而攜載來自 第一資料管線及本地服務插入管線的資料符號，而於其他 框中則否。更特別地，於其他範例中，接收器可被配置以 於其已被指定給該基地站之分時多工框中，接收其使用第 二調變架構而攜載來自第一資料管線及本地插入管線的資 料符號之OFDM符號，而於其他框中則否。因此，藉由使 用第二調變架構以在共同無線電頻率載波上傳輸OFDM符 號至一接收器（其係從使用第一調變架構所調變的OFDM 符號檢測並復原該些資料符號）所造成的「干擾」數量將 正比於各叢集中之基地站數目而被減少。此處所使用之用 語「干擾」的意義在於：具有依據第二調變架構而調變之 副載波的OFDM符號將減少一接收器之信號雜訊比，該接 收器係檢測由具有依據第一調變架構而調變之副載波的 OFDM符號所攜載的資料符號，因爲如上所述，一種層式 調變配置之性質將會增加雜訊至一接收器。 本發明之各種進一步形態及特徵被界定於後附申請專 利範圍中，並包括一種接收方法。 1 式 方 施 實 如上所述，本發明之實施例欲提供（於一應用中）一 種配置，其中本地內容可被傳輸於單頻網路中，而同時容 •10- 201214986 許網路之其他部分仍接收主要廣播信號。一範例說明是其 中本地內容與國家廣播電視節目需被同時地廣播。 圖1提供基地站BS之網路的範例說明，基地站BS係依 據一共同調變的OFDM信號以經由傳輸天線1傳輸一信號。 基地站BS被配置遍及一邊界2內之地理區域，該邊界2於一 範例中可爲國界。如以上所解釋，於單頻網路架構中，所 有基地站BS係於相同時間以相同頻率廣播相同的OFDM信 號。行動裝置Μ可從任何基地站接收OFDM信號。更特別 地，行動裝置Μ亦可從其他基地站接收相同的信號，因爲 信號係同時地廣播自邊界2所識別之區域內的所有基地站 。此種所謂的傳輸多樣性配置是單頻OFDM網路所常見的 。作爲一種從OFDM符號復原資料之接收器中的OFDM信號 之檢測的部分，於檢測程序中結合來自所傳輸之OFDM符 號的能量，該些OFDM符號係針對來自不同來源之各符號 而被接收。因此，傳輸來自不同基地站之相同信號可增進 正確地復原由OFDM符號所傳遞之資料的可能性，假設其 所接收的OFDM符號或該OFDM符號的回波之任何分量係落 入網路部署所容許之總防護間隔週期內。 如圖1中所示，於某些範例中，基地站BS可由一或更 多基地站控制器BSC所控制，基地站控制器BSC可控制基 地站之操作。於某些範例中，基地站控制器BSC可控制與 一地理區域有關的網路之一部分內的一或更多基地站。於 其他範例中，基地站控制器BSC可控制基地站之一或更多 叢集，以致本地內容之傳輸係針對分時多工框而配置。 -11 - 201214986 以國。 S ，，B 界中站 國例地 於範基 應一 之 相於示 可，所 域來中 區一 1 之此圖 別如Ji 識。f 所路傳 2 網被 界家各 邊國號 由爲信 ， 路視 述網電 所之的 上站播 如地廣 基性 致家 關他 有其 , 非 題而 問站 術地 技基 - 些 論某 討之 於示 在所 的中 巨 1 的圖 例自 施來 實輸 之傳 明以 發用 本種 ，一 而供 然提 基地站的本地廣播信號之配置。此一配置之一範例可爲： 假如與一特別區域有關的本地廣播新聞或交通新聞係廣播 自某些基地站而非其他基地站。於一種多頻網路中，此係 微不足道的，因爲本地廣播之信號可以不同頻率被傳輸自 不同傳輸器，而因此可無關於從其他基地站所廣播之信號 來檢測。然而，於單頻網路中，需提供一種技術以容許針 對某些基地站而非其他基地站之內容的本地服務插入。 如上所述，先前技術文件US 2008/0159186係揭露一 種技術，用以結合兩種調變架構來形成一調變層給複數資 料源之每一個。一種實施此一配置之傳輸器係顯示於圖2 。於圖2中，資料係從第一資料管線4及第二資料管線6被 饋送至一調變器8，其係將資料調變至副載波上以形成 OFDM符號。該調變被執行以使得來自第一資料管線4之資 料與來自第一和第二資料管線4、6兩者之資料可被分離地 檢測。一OFDM符號形成器1〇接著形成〇fDM符號於頻率領 域（如於調變器8之輸出處所提供者），並藉由依據OFDM 調變器/傳輸器之習知操作以執行反傅立葉轉換而將頻率 領域的OFDM符號轉變爲時間領域。時間領域的〇fdM符號 被接著饋送至一無線電頻率調變器12，其將OFDM符號向 -12- 201214986 上轉變至一無線電頻率載波信號上以致OFDM信號可被傳 輸自一天線14。 US 2008/01 591 86中所揭露之技術係顯示於圖3&及3b 中。圖3a及3b提供在包含同相I及正交相Q分量之複數平面 中的信號群集點之圖示。圖3a中所示之範例群集點係用於 QPSK，而圖3b中所示之範例係用於16QAM。依據用以獲 得多層調變之已知技術，來自兩來源之資料被調變至第二 調變架構之信號群集點上。第二調變架構之信號群集點代 表可用於調變架構之可能的調變符號値。針對圖3a中所示 之第一調變架構，QPSK之信號群集點被提供爲小圓圏 “〇”20。如此一來，來g來源B之位元（其係提供自來源資 料管線6 )被映射至如圖3 a中所示之信號群集點上，以致 各可能的調變信號値係代表來自來源bOb 1之兩位元，以（ 例如）使用灰階編碼之習知方式。 圖3b中所示之第二調變架構爲16QAM，其提供以“X” 表示之16個可能的信號群集點22。除了藉由來自第一資料 管線6之資料的信號之調變（其係顯示爲bOb 1 )以外，來 自圖3b中之每一四個象限的群集點之一的選擇亦識別針對 値aOa 1之來自第二來源資料管線4之兩位元的四個可能値 之一。因此，圖3b中所示的信號點之一的檢測將不僅識別 aOal之値，亦同時識別bOb 1之値，其係根據信號點係從四 個象限之哪個所檢測。因此，可進行一種多層調變架構。 傳輸器 -13- 201214986 本發明之實施例係提供一種配置，其利用依據US 2008/0159186之多層調變架構以提供針對本地內容之本地 廣播服務’而同時仍容許附近區域中之基地站檢測國家廣 播信號。 圖4顯示一種實現本發明之傳輸器，其可被用以插入 本地內容於圖1中所示的基地站之一上。於圖4中，複數η 個實體層資料管線（PLP ) 30被配置以饋送傳輸之資料至 一排程器34。亦提供一發信資料處理管線36，於每一管線 中’從一輸入38接收資料給一特定頻道，於一前向錯誤校 正編碼器40，其被配置以（例如）依據低密度同位檢査（ LDPC )碼來編碼資料。該些編碼的資料符號被接著饋送 入一交錯器42，其將已編碼的資料符號交錯以增進藉由編 碼器40所使用之LDPC碼的性能。 排程器34接著將來自每一資料管線3〇以及發信處理管 線36之每一調變符號結合成資料框以便映射至OFDM符號 上。排程的資料被提呈至一資料片處理單元50、51、52， 其包括一頻率交錯器54、一本地引導產生器180、一調變 器182、一選擇性的MISO處理單元184及一引導產生器56 。資料片處理器將資料分配給一既定的PLP以使得其將僅 佔據OFDM符號之某些副載波。從資料片處理單元50、51 ' 52所輸出之資料被接著饋送至分時多重存取（TDM A ) 定框單元58。TMDA定框單元58之輸出係饋至一OFDM調變 器70，其產生時間領域中之OFDM符號，其接著藉由一 RF 調變器72而被調變至一無線電頻率載波信號上並接著被饋 -14 - 201214986 送至一用於傳輸之天線74。 如以上所解釋，本發明之實施例提供一種技術，用以 容許本地內容被廣播自一關於由圖丨所示之網路所覆蓋的 國家區域之本地區域內的一或更多基地站。至此，圖4中 所示之傳輸器亦包括一本地服務插入資料片處理器80，其 包括一頻率交錯器54及一本地引導產生器180。然而，此 外’依據本發明，資料片處理器50中所示之調變器44具有 一用以接收來自本地服務插入資料片處理器80之資料的第 二輸入。依據本發明，調變器44係依據第二調變架構以將 本地服務插入資料調變至信號群集點之一相關組。如稍後 參考圖5及6將解釋者：第二調變架構（其被用於本地內容 以及主要資料）之信號群集點係關連於第一調變架構（其 僅被用於傳遞來自PLP管線η之主要資料）之群集點。 如圖4中所示，調變器44具有一第一輸入82，其接收 來自資料片處理器50之資料、及一第二輸入84，其接收來 自本地服務插入資料片處理器80之資料。於以下描述中， 來自資料片處理器50之資料將被稱爲第一或主要資料管線 。於一範例中，來自資料片處理器50之資料係攜載一國家 廣播頻道，其將被傳遞遍及圖1之整個網路。 調變器44被更詳細地顯示於圖5中。如圖5中所示，來 自本地服務插入管線80之資料係從第二輸入84被饋送入一 第一資料字元形成器90。來自第一資料管線之資料（當接 收於資料字元形成器92中時）被配置以形成位元y0yly2y3 之四個族群，以供映射至一符號選擇器94內之16QAM調變 -15- 201214986 符號的16個可能値之一上。類似地，資料字元形成器9〇將 來自第一資料管線82之資料形成爲包含四個位元y〇yly2y3 之資料字元。然而，資料字元形成器90亦接收來自本地服 務插入管線80之資料符號而因此將來自本地服務插入資料 管線8 4之兩個位元附加至來自第一資料管線8 2之資料位元 ，以形成六位元資料字元y0yly2y3h0hl，其中四個位元 y0yly2y3係來自第一資料管線32之符號串而兩個位元hOhl 係來自本地服務插入管線80，因而形成六位元字元以便選 擇64QAM ( 26 = 64 )的64個可能調變符號値之一。 一符號選擇器96被配置以接收六位元字元 y0yly2y3h0hl，並依據該字元之値以選擇64QAM調變架構 的64個可能値之一，以於一輸出96.1形成64QAM符號之一 串流。來自符號選擇器94、96之個別輸出被接著饋送至一 開關單元98，其亦在控制輸入100上接收一有關來自本地 服務插入管線90之本地內容何時出現且將被廣播自基地站 的指示。假如本地服務插入資料將被廣播自基地站，則開 關98被配置以選擇來自64Q AM符號選擇器96之輸出96.1。 反之，則開關被配置以選擇來自16Q AM符號選擇器94之輸 出94_1。調變符號因此被輸出自調變器44以便傳輸於一輸 出頻道102之OFDM符號上。 控制輸入1 〇〇可（於某些範例中）提供一控制信號， 其指示本地內容何時被傳輸自本地服務插入資料片處理器 80。控制輸入1 00中所提供之控制信號可被產生自一基地 站控制器，其係連接至基地站內之傳輸器。 -16- 201214986 於其他範例中，發信資料處理管線36可被配置以經由 L1發信資料傳遞一有關本地服務插入管線80何時正在或將 要傳輸本地資料的指示。因此，接收器可復原或可檢測並 復原L1發信資料以及決定本地內容何時或是否正在被或將 要被傳輸。另一方面，接收器可被提供一資料，其係藉由 某其他手段以提供本地內容資料何時將被傳輸之排程，諸 如藉由編程該接收器。 基地站之發展 圖6提供一種可於圖1中產生之配置的範例圖示，其中 —第一基地站BS 110可傳輸來自第一資料管線32之資料於 —細胞A內，而一相鄰的基地站BS 112可傳輸資料於一第 二細胞B內，所傳輸之資料包括來自第一資料管線32之資 料連同來自本地服務插入管線80之本地服務插入資料。因 此，來自細胞A之基地站110正傳輸一使用16QAM以調變其 副載波之OFDM符號，而來自細胞B之基地站1 12正傳輸藉 由64QAM以調變其副載波之OFDM符號。因此，如圖6中之 位元排序所顯示，最後兩位元hOhl被用以選擇依據64QAM 之信號群集點的較精細的細節，而位元y0yly2y3被用以選 擇複數平面內較粗略格柵中的16Q AM符號之信號群集點。 如先前已解釋的’細胞A和B內之基地站1 1〇、Π2將於 相同的頻率上傳輸OFDM符號。如此一來，一行動終端中 之接收器將接收一結合的OFDM信號’如同（部分地）信 號正經由一多重路徑環境中之不同路徑而被接收。然而’ -17- 201214986 從細胞A內之基地站110所傳輸的OF DM信號包含使用第一 調變架構16QAM所調變的OFDM符號，而從細胞B內之基 地站1 12所傳輸的OFDM符號將使用第二調變架構64Q AM而 被調變。於行動終端內之接收器上，以第一調變架構及第 二調變架構所接收之OFDM符號的總功率之比例將取決於 行動裝置Μ與細胞A和B內之每一傳輸器的接近度。再者， 從第一資料管線及本地服務插入管線正確地復原資料符號 之可能性將取決於接收器所能夠檢測依據從細胞A所傳輸 之第一調變架構16Q AM的OFDM符號或依據從細胞B所傳 輸之64QAM的OFDM符號之程度，在個別以第二和第一調 變架構所調變之OFDM信號存在時。 如圖7所示，可能的模擬信號群集値之三個圖表120、 122、124被顯示於16QAM及64QAM之範例，其被顯示於圖 8中之範例。第一個左手邊圖表120提供所接收之調變信號 値的複數平面，當細胞A和B之基地站110、112中的傳輸器 正傳輸具有個別以16QAM和64QAM調變架構調變之副載波 的OFDM符號時，因爲細胞B正傳輸本地服務插入資料。第 —圖表120係相應於位於位置X上之行動裝置，其係假設所 接收之信號功率的8 0%來自細胞A而所接收之信號功率的 20%來自細胞B。如可從圖7中所見，圖表120係提供依據 16Q AM接收之信號的離散信號點，但由於來自細胞B (其 係傳輸64QAM調變符號）之20%功率所造成的可能點之分 佈而有雜訊的顯著增加。 相應地，圖表122提供複數平面中之信號値的圖表， -18- 201214986 當接收器位於位置Y上，並假設所接收之功率的60%來自 細胞Α而所接收之功率的4 0%來自細胞Β。如可從圖中看出 ’雖然信號群集圖表被群集爲相應於一與16QAM符號之每 一可能値的關連之叢集，但離散的群集點已依據64Q AM調 變架構而被形成》因此，可理解假如信號雜訊比夠高，則 一位於位置Y上之接收器可檢測64QAM信號點之一且因而 復原本地插入資料。相應地，右手邊的圖表124係顯示位 置Z上之情況，其係假設（例如）僅有信號功率之10%來 自細胞A而信號功率之90%來自細胞B »因此，如圖表124 中所示，清楚地每一 64Q AM信號群集點均可用於檢測及復 原資料，其被產生於第一資料管線及本地服務插入資料管 線。因此，應理解：根據接收器之位置，一行動終端可復 原本地傳輸之資料及傳輸自第一資料管線之資料（例如國 家廣播），當位於細胞B中或其附近時，而於細胞A中，則 一接收器仍將能夠復原來自第一資料管線之資料。使用由 64Q AM信號之第二調變架構和第一調變架構16Q AM所提供 的階層式調變之效果將不會中斷國家廣播之資料的接收， 當本地廣播的資料被傳輸自一相鄰細胞時。 TDMA本地服務插入 本發明之一些實施例可使用之進一步強化是將本地服 務傳輸分配於相鄰細胞的叢集之間，以達成在不同時刻於 不同細胞中傳輸其使用高階（第二）調變架構所傳輸之內 容的功效。參考圖9a、9b及9c以說明此技術。 -19- 201214986 於圖9a中，顯示四個細胞之—叢集。這些細胞被顯示 以不同等級的陰影且被個別標示以Τχ1、Τχ2、Tx3、Tx4 β因此’圖9a顯不四個細胞之—叢集。如將理解者：除了 接收來自第一资料管線的資料（其可爲，例如，國家廣播 頻道）以外’亦可使用結合高階階層式調變架構之本地資 料插入管線以提供一地區性廣播，如以上所解釋。然而， 如以上所解釋，當使用第二或較高調變架構時，效果係帶 來雜訊或干擾，其會減少接收來自第一通訊頻道之資料（ 其爲使用第一或低階調變架構之國家廣播）的接收器之信 號雜訊比。更明確地’例如，假如來自第一資料管線之國 家廣播信號係使用QPSK來調變，且結合的第一通訊頻道 與本地服務插入頻道被調變至16Q AM之第二或高階調變架 構上，則16QAM將出現針對一嘗試接收以QPSK調變架構 調變之OFDM符號的接收器增加其雜訊的現象。 爲了減少由第二/高階調變架構（16Q AM )相對於第 一 /低階調變架構（QPSK )所造成的干擾量，其廣播 OFDM信號之細胞被聚集如圖9a中所示。再者，圖9a中所 示之四個細胞叢集內的傳輸器以框接框之方式輪流廣播高 階的16QAM調變信號，其係提供來自第一資料通訊管線和 其本地服務插入管線之資料符號。此一配置被顯示於圖9b 中〇 於圖9b中，顯示由四個實體層框所構成的TDMA框。 實體層框被標示框1、框2、框3及框4。於各實體層框內， OFDM信號傳遞來自各個PLP之資料。如以上所解釋’與使 -20- 201214986 用QPSK之第一資料管線的資料傳輸同時地，攜載來自第 一資料管線和本地服務插入管線之資料的OFDM符號亦使 用（例如）16QAM而被傳輸。然而，爲了減少由16QAM調 變所造成之干擾，於四個細胞之叢集內僅有傳輸Txl、Tx2 、Τχ3、Τχ4之一被容許傳輸具有高階16QAM調變的副載波 之OFDM符號，於TDMA框之各實體層框期間。因此，於實 體層框1中，僅有Txl傳輸具有以16QAM調變之副載波的 OFDM符號，以提供來自結合的第一資料管線和其本地服 務插入管線之資料；而於框2中，僅有Tx2傳輸具有16Q AM 之OFDM符號；以及之後，TX3於框3及TX4於框4。接著該 型態重複於下個TDMA框。於各情況下，所有其他的傳輸 器傳輸以QPSK調變之OFDM符號或用於僅攜載第一資料管 線之群集。 由於對四個傳輸器Txl、Tx2、Tx3、Tx4的每個之間 的本地服務插入資料之傳輸進行時間分割，有效地達成本 地資料率爲第一資料管線之資料率的四分之一。因此，各 細胞係傳輸本地服務插入內容於每第四個實體層框。然而 ，相應地，因爲高階調變架構僅從一細胞傳輸一次於每四 個框，所以相應地減少了由位於希望接收第一 /低階調變 架構（QPSK )之四個細胞的涵蓋區域中之接收器所經歷 的有效干擾。因此，於圖9c所示之細胞的型態中’由本地 服務插入資料所造成且將出現對接收器增加了雜訊的干擾 被分佈遍及四個細胞之叢集。因此，減少了由本地服務插 入資料所造成之相對干擾或增加的雜訊。此可被視爲相當 -21 - 201214986 於多頻網路中之頻率再使用。針對圖9a、9b、9c中所示之 範例，下表代表以每一第一（1 6QAM )和第二（64QAM ) 調變架構之OFDM符號的傳輸：201214986 VI. Description of the Invention: [Technical Field] The present invention relates to a transmitter for transmitting data via orthogonal frequency division multiplexing (OFDM) symbols, wherein the data is provided by a plurality of data from different complexes. Embodiments of the present invention have found applications for receiving data transmitted using OFDM symbols that are transmitted using a communication system that includes a plurality of base stations configured throughout a geographic area. In some embodiments, the communication system is configured to broadcast video, audio or data. [Prior Art] Orthogonal Frequency Division Multiplexing (OFDM) is a modulation technique that has been found to be extremely advantageous in communication systems, such as, for example, those designed to be based on first and second generation digital video broadcasting terrestrial standards (DVB). -T/T2) operates a communication system; and is also proposed for a fourth generation communication system also known as Long Term Evolution (LTE). OFDM can be generally described as providing parallel-modulated K-narrow-band subcarriers (where κ is an integer), each subcarrier transmitting a modulated data symbol, such as a quadrature amplitude modulation (QAM) modulation symbol or four-phase Shift keying (QPSK) modulation symbol. The modulation of the subcarriers is formed in the frequency domain and transformed into a time domain for transmission. Since the data symbols are transmitted in parallel on the subcarriers, the same modulated symbols can be passed on each subcarrier for an extended period of time which is longer than the coherence time of the radio channel. The subcarriers are modulated in parallel at the same time, so that the OFDM symbol is formed by combining the modulated carrier -5 - 201214986. The OFDM symbol thus comprises a plurality of subcarriers, each of which is modulated simultaneously with a different modulation symbol. In the next generation of handheld (NGH) television systems, OFDM has been proposed to deliver television signals from base stations deployed throughout a geographic area. In some examples, the NGH system will form a network in which multiple base stations simultaneously transmit OFDM symbols on the same carrier frequency, thereby forming a so-called single frequency network. Due to some properties of OFDM, a receiver can receive OFDM symbols from two or more different base stations, which can then be incorporated into the receiver to improve the integrity of the transmitted data - although single frequency networks There is an advantage in the improved integrity of the operation and delivery of the data, but it also has a disadvantage if it is required to transmit local data of a part of the geographical area. For example, it is well known in the UK that national carrier (BBC) broadcast television news spreads throughout the national network, but then switches to "local news" at certain times, where local news programs are transmitted specifically for local areas within the national network. . However, the UK operates a multi-frequency DVB_T system, so that the insertion of local news or any kind of local content is not important, since different zones transmit DVB-T television signals at different frequencies and therefore the TV receiver only adjusts to this The appropriate carrier frequency of the zone without interference from other zones. However, there is a technical problem in providing a configuration in a single frequency network to locally insert data. A known technique for providing a hierarchical or multi-layer modulation architecture in a single frequency OFDM network has been disclosed in U.S. Patent Application Serial No. 4/0,159,186. Hierarchical Modulation architecture provides a complex modulation layer that can be used to simultaneously pass data from different sources or pipelines. -6- 201214986 SUMMARY OF THE INVENTION In accordance with the present invention, a receiver is provided for receiving and recovering data symbols from orthogonal frequency division multiplexing (OFDM) symbols. The 〇fdm symbols include a plurality of subcarrier symbols formed in the frequency domain and modulated by the data symbols to be transmitted, wherein the data symbols have been received for transmission from the first data pipeline, or the first data pipeline and Locally inserted into the OFDM symbol of the pipeline, and if the data symbols have been received from the first data pipeline, then the data symbols are modulated to the subcarriers of the OFDM symbols using a first modulation architecture Or if the data symbols have been received from the first data pipeline and the local insertion pipeline, the data symbols are modulated to the subcarriers of the OFDM symbols using a second modulation architecture . The receiver includes a tuner configured to detect a radio frequency signal representative of the OFDM symbols and to form a baseband signal representative of the OFDM symbols, an OFDM detector configured to operate The modulation symbols from the subcarriers of the baseband OFDM symbols are restored, and a demodulator is recovered. The demodulator is configured to receive the modulated symbols during operation and to generate an output string of the data symbols of the first data pipeline from the modulated symbols on the first output according to a control signal Generating, on the first output, the output string of the data symbols of the first data pipeline from the modulation symbols and generating an output string of the data symbols of the local insertion pipeline on the second output, wherein the first modulation architecture is low a tone modulation architecture that provides a first modulation symbol from a complex number of cluster points in the complex plane that is less than the second modulation architecture (which is a high-order modulation architecture) 201214986, the second modulation architecture providing The second modulation symbol is configured to be associated with the corresponding modulation of the first modulation architecture in the complex plane, and the effect is that the detection of one of the second modulation symbols of the second modulation architecture is Providing a data symbol from the local insertion pipeline and/or the first data pipeline, and permitting detection of a first modulation symbol from the first modulation architecture (which provides data symbols from the first data pipeline) In response to the modulation symbol from the second modulation architecture, a complex modulation layer is provided to the modulator. Furthermore, the demodulator is configured to generate the data symbols by identifying the cluster points according to the first modulation architecture and generating the first data pipeline corresponding to the identified cluster points during operation The data symbols of the first data pipeline, and/or by identifying a cluster point according to the second modulation architecture and generating a data symbol of the first data pipeline and the local insertion pipeline corresponding to the identified cluster point Generating the data symbols of the first data pipeline and the local insertion pipeline. The control signal indicates to the demodulator that the data symbols from the local insertion pipeline have been transmitted in the received OFDM symbols as disclosed in US 2008/0159186 (published on July 3, 2008). Configuration, single carrier frequency OFDM network is provided with a facility for simultaneously forming a plurality of different modulation "layers" by transferring data from different pipelines using two related modulation architectures. As will be explained later, the first modulation architecture is selected to transfer data from the first data pipeline, and the second modulation architecture associated with the first modulation architecture is selected to be based on the first and second communication pipelines. 201214986 to pass the information. The first modulation architecture includes the number of cluster points added in the complex plane as compared to the first modulation architecture. In accordance with an exemplary embodiment of the present invention, a receiver is configured to receive data symbols from the first data line 'or the first data line and the local data line. The receiver is thus configured to detect and recover data from OFDM symbols transmitted by a communication system configured such that - or more base stations from which the plurality of base stations forming a communication network are selected to be selected The OFDM symbol having the subcarrier modulated according to the second modulation architecture transmits the local content. Thus, the second modulation architecture is used to communicate the data symbols from the first data pipeline and the local insertion pipeline. Due to the configuration of the second modulation architecture relative to the first modulation architecture, the data symbols from the first data pipeline can be received even when transmitted on the same radio carrier because from the first modulation The detection of the cluster point of the architecture will require a lower signal to noise ratio than the second modulation architecture. This is because the first modulation architecture forms a cluster point secondly on the complex plane of the second modulation architecture, which can be regarded as a more coarse version of the second modulation architecture, such that the complex plane is interposed The difference between the cluster points of the first modulation symbol allows the data from the first data pipeline to be more easily recovered. Furthermore, because other base stations may not be transmitting local service insertion pipeline data, the receivers (in the geographic area in which these other base stations are configured) will still be able to detect data from the first data pipeline. This is because, for a detector that detects OFDM symbols according to the first modulation architecture, an OFDM signal transmitted from a neighboring base station on a common radio frequency carrier using a second modulation architecture will only appear as a hybrid. News. As a result of 201214986, an efficient and efficient method of inserting local content in a single frequency network is provided. In some examples, the receiver can be configured to receive OFDM symbols in some time division multiplex frames, using the second modulation architecture to carry data symbols from the first data pipeline and the local service insertion pipeline And in other boxes, no. More particularly, in other examples, the receiver can be configured to receive from the first data pipeline and locally using the second modulation architecture in the time-sharing multiplex box that has been assigned to the base station Insert the OFDM symbol of the data symbol of the pipeline, but not in other boxes. Thus, by using a second modulation architecture to transmit OFDM symbols on a common radio frequency carrier to a receiver that detects and recovers the data symbols from OFDM symbols modulated using the first modulation architecture The number of "interferences" will be reduced proportional to the number of base stations in each cluster. The term "interference" as used herein means that an OFDM symbol having subcarriers modulated according to a second modulation architecture will reduce the signal to noise ratio of a receiver that is detected by the first tone. The data symbols carried by the OFDM symbols of the sub-carriers of the variable architecture are modulated, as described above, the nature of a layered modulation configuration will increase the noise to a receiver. Various further aspects and features of the present invention are defined in the scope of the appended claims and include a receiving method. Embodiments of the Invention As described above, embodiments of the present invention are intended to provide (in an application) a configuration in which local content can be transmitted in a single frequency network while at the same time accepting the other The part still receives the main broadcast signal. An example is where local content and national broadcast television programs need to be broadcast simultaneously. Figure 1 provides an illustration of a network of base station BSs that transmit a signal via transmission antenna 1 in accordance with a commonly modulated OFDM signal. The base station BS is configured throughout a geographic area within a boundary 2, which may be a national boundary in one example. As explained above, in a single frequency network architecture, all base station BSs broadcast the same OFDM signal at the same frequency at the same time. The mobile device can receive OFDM signals from any base station. More specifically, the mobile device can also receive the same signal from other base stations because the signals are simultaneously broadcast from all base stations in the area identified by boundary 2. This so-called transmission diversity configuration is common in single-frequency OFDM networks. As part of the detection of the OFDM signal in the receiver of the OFDM symbol recovery data, the energy from the transmitted OFDM symbols is combined in the detection procedure, the OFDM symbols being received for symbols from different sources. Therefore, transmitting the same signal from different base stations can increase the likelihood of correctly restoring the data transmitted by the OFDM symbol, assuming that the received OFDM symbol or any component of the echo of the OFDM symbol falls into the network deployment. Allow for the total guard interval period. As shown in Figure 1, in some examples, the base station BS can be controlled by one or more base station controllers BSC, which can control the operation of the base station. In some examples, the base station controller BSC can control one or more base stations within a portion of the network associated with a geographic area. In other examples, the base station controller BSC can control one or more of the base stations such that the transmission of local content is configured for time-sharing multiplex frames. -11 - 201214986 By country. S,, B, the middle station, the country, and the country, in the case of Fan Ji, should be in the same position, and the picture in the middle of the area is like Ji. f The road 2 network is bounded by the national number of each side of the border, and the road to the net station of the station has a wide-ranging basis to give him a home, and it is not a question. On the illustration of the Zhongju 1 in the show, the description of the local broadcast signal from the base station is given by the use of this kind. An example of such a configuration would be: If local broadcast news or traffic news related to a particular area is broadcast from certain base stations rather than other base stations. In a multi-frequency network, this is negligible because the locally broadcast signals can be transmitted from different transmitters at different frequencies, and thus can be detected without signal from other base stations. However, in single frequency networks, a technique is needed to allow local service insertion for content at certain base stations rather than other base stations. As described above, the prior art document US 2008/0159186 discloses a technique for combining a two modulation architecture to form a modulation layer for each of a plurality of data sources. A transmitter implementing this configuration is shown in FIG. In Figure 2, data is fed from a first data line 4 and a second data line 6 to a modulator 8, which modulates the data onto subcarriers to form OFDM symbols. The modulation is performed such that the data from the first data line 4 and the data from both the first and second data lines 4, 6 can be detected separately. An OFDM symbol former 1〇 then forms a 〇fDM symbol in the frequency domain (as provided at the output of the modulator 8) and performs an inverse Fourier transform by conventional operations in accordance with the OFDM modulator/transmitter. Convert OFDM symbols in the frequency domain into time domains. The 领域fdM symbol of the time domain is then fed to a radio frequency modulator 12 which converts the OFDM symbol onto -12-201214986 onto a radio frequency carrier signal such that the OFDM signal can be transmitted from an antenna 14. The technology disclosed in US 2008/01 591 86 is shown in Figures 3 & and 3b. Figures 3a and 3b provide illustrations of signal cluster points in a complex plane containing in-phase I and quadrature-phase Q components. The example cluster points shown in Figure 3a are for QPSK, while the example shown in Figure 3b is for 16QAM. Based on known techniques for obtaining a multi-layer modulation, data from two sources is modulated to the signal cluster point of the second modulation architecture. The signal cluster point representation of the second modulation architecture can be used to modulate the possible modulation symbols of the architecture. For the first modulation architecture shown in Figure 3a, the signal cluster point of QPSK is provided as a small circle "〇" 20. In this way, the bits from source G (which are provided from source data pipeline 6) are mapped to the signal cluster points as shown in Figure 3a, such that each possible modulation signal is represented by the source bOb. A two-digit one is used, for example, in the conventional way of using grayscale coding. The second modulation architecture shown in Figure 3b is 16QAM, which provides 16 possible signal cluster points 22 represented by "X". In addition to the modulation of the signal from the data from the first data pipeline 6, which is shown as bOb 1 , the selection of one of the cluster points from each of the four quadrants in Figure 3b is also identified for 値aOa 1 One of the four possible defects from the two elements of the second source data pipeline 4. Thus, the detection of one of the signal points shown in Figure 3b will not only identify the ao, but also the bOb 1, which is detected from which of the four quadrants depending on the signal point. Therefore, a multi-layer modulation architecture can be implemented. Transmitter-13 - 201214986 Embodiments of the present invention provide a configuration that utilizes a multi-layer modulation architecture in accordance with US 2008/0159186 to provide local broadcast services for local content while while still allowing base stations in nearby areas to detect countries Broadcast signal. Figure 4 shows a transmitter embodying the present invention that can be used to insert local content on one of the base stations shown in Figure 1. In Figure 4, a plurality of n physical layer data lines (PLPs) 30 are configured to feed the transmitted data to a scheduler 34. A signaling data processing pipeline 36 is also provided, in each of the pipelines 'receiving data from an input 38 to a particular channel, to a forward error correction encoder 40, which is configured, for example, in accordance with a low density parity check ( LDPC) code to encode data. The encoded data symbols are then fed into an interleaver 42 which interleaves the encoded data symbols to enhance the performance of the LDPC code used by the encoder 40. Scheduler 34 then combines each modulated symbol from each data line 3 and the transmit processing line 36 into a data frame for mapping onto the OFDM symbol. The scheduled data is presented to a slice processing unit 50, 51, 52, which includes a frequency interleaver 54, a local boot generator 180, a modulator 182, a selective MISO processing unit 184, and a Boot generator 56. The data slice processor allocates the data to a given PLP such that it will only occupy some of the subcarriers of the OFDM symbol. The data output from the slice processing unit 50, 51' 52 is then fed to the Time Division Multiple Access (TDM A) framing unit 58. The output of the TMDA framing unit 58 is fed to an OFDM modulator 70 which produces OFDM symbols in the time domain which are then modulated by an RF modulator 72 onto a radio frequency carrier signal and then Feed-14 - 201214986 is sent to an antenna 74 for transmission. As explained above, embodiments of the present invention provide a technique for allowing local content to be broadcast from one or more base stations within a local area of a country area covered by the network shown. To this end, the transmitter shown in FIG. 4 also includes a local service insertion data slice processor 80 including a frequency interleaver 54 and a local boot generator 180. However, in accordance with the present invention, the modulator 44 shown in the slice processor 50 has a second input for receiving data from the local service insertion slice processor 80. In accordance with the present invention, modulator 44 is responsive to a second modulation architecture to modulate local service insertion data to a related group of signal cluster points. As will be explained later with reference to Figures 5 and 6, the signal clustering point of the second modulation architecture (which is used for local content and primary data) is related to the first modulation architecture (which is only used to pass from the PLP pipeline) The main point of η) the cluster point. As shown in FIG. 4, modulator 44 has a first input 82 that receives data from data sheet processor 50 and a second input 84 that receives data from local service insertion data slice processor 80. In the following description, the material from the slice processor 50 will be referred to as the first or primary data pipeline. In one example, the data from the data slice processor 50 carries a national broadcast channel that will be delivered throughout the network of Figure 1. Modulator 44 is shown in more detail in FIG. As shown in Figure 5, data from the local service insertion pipeline 80 is fed from a second input 84 into a first data character former 90. The data from the first data pipeline (when received in data character former 92) is configured to form four populations of bits y0yly2y3 for mapping to 16QAM modulation in a symbol selector 94 -15 - 201214986 One of the 16 possible symbols of the symbol. Similarly, the data character former 9 形成 forms the data from the first data pipeline 82 into data characters containing four bits y〇yly2y3. However, the data character former 90 also receives the data symbols from the local service insertion pipeline 80 and thus appends the two bits from the local service insertion data pipeline 84 to the data bits from the first data pipeline 8 2 to A six-bit data character y0yly2y3h0hl is formed, wherein four bits y0yly2y3 are from the symbol string of the first data pipeline 32 and two bits hOhl are from the local service insertion pipeline 80, thus forming a six-bit character to select 64QAM ( 26 = 64) One of the 64 possible modulation symbols 値. A symbol selector 96 is configured to receive the six-bit character y0yly2y3h0hl and select one of the 64 possible frames of the 64QAM modulation architecture based on the one of the characters to form a stream of one of the 64QAM symbols at an output 96.1. The individual outputs from symbol selectors 94, 96 are then fed to a switch unit 98, which also receives an indication on control input 100 as to when local content from local service insertion pipeline 90 is present and will be broadcast from the base station. If the local service insertion data is to be broadcast from the base station, the switch 98 is configured to select the output 96.1 from the 64Q AM symbol selector 96. Conversely, the switch is configured to select the output 94_1 from the 16Q AM symbol selector 94. The modulation symbols are thus output from the modulator 44 for transmission on the OFDM symbols of an output channel 102. Control input 1 (in some examples) provides a control signal indicating when local content is transmitted from the local service insertion slice processor 80. The control signals provided in control input 100 can be generated from a base station controller that is coupled to a transmitter within the base station. -16- 201214986 In other examples, the dispatch material processing pipeline 36 can be configured to communicate via the L1 dispatch data an indication of when the local service insertion pipeline 80 is or will transmit local data. Thus, the receiver can recover or detect and recover the L1 signaling material and determine when or if local content is being or will be transmitted. Alternatively, the receiver can be provided with a profile by some other means to provide a schedule of when the local content material will be transmitted, such as by programming the receiver. Development of Base Station FIG. 6 provides an exemplary illustration of a configuration that can be generated in FIG. 1, wherein the first base station BS 110 can transmit data from the first data line 32 within the cell A, while an adjacent The base station BS 112 can transmit data to a second cell B, the transmitted data including data from the first data line 32 along with local service insertion data from the local service insertion line 80. Thus, base station 110 from Cell A is transmitting an OFDM symbol that uses 16QAM to modulate its subcarriers, while base station 1 12 from Cell B is transmitting OFDM symbols that are modulated by 64QAM to its subcarriers. Therefore, as shown by the bit ordering in Figure 6, the last two bits hOhl are used to select the finer details of the clustering points according to the signal of 64QAM, and the bit y0yly2y3 is used to select the coarser grid in the complex plane. The signal cluster point of the 16Q AM symbol. The base stations 1 1 〇, Π 2 within cells A and B, as previously explained, will transmit OFDM symbols on the same frequency. As such, the receiver in a mobile terminal will receive a combined OFDM signal as if (partially) the signal was being received via a different path in a multipath environment. However, the -11-201214986 OF DM signal transmitted from the base station 110 within the cell A contains the OFDM symbol modulated using the first modulation architecture 16QAM, and the OFDM symbol transmitted from the base station 12 in the cell B. It will be modulated using the second modulation architecture 64Q AM. The ratio of the total power of the OFDM symbols received by the first modulation architecture and the second modulation architecture to the receiver within the mobile terminal will depend on the proximity of the mobile device to each of the transmitters A and B. degree. Furthermore, the possibility of correctly recovering the data symbols from the first data pipeline and the local service insertion pipeline will depend on the receiver being able to detect the OFDM symbols based on the first modulation architecture 16Q AM transmitted from the cell A or from the cells. The extent of the 64QAM OFDM symbol transmitted by B is present in the presence of an OFDM signal modulated by the second and first modulation architectures. As shown in Figure 7, three graphs 120, 122, 124 of possible analog signal clusters are shown in the examples of 16QAM and 64QAM, which are shown in the example of Figure 8. The first left-hand side graph 120 provides the complex plane of the received modulated signal ,, when the transmitters in the base stations 110, 112 of cells A and B are transmitting subcarriers with individual modulations modulated by 16QAM and 64QAM modulation architectures. The OFDM symbol is inserted because the cell B is transmitting the local service insert. The first graph 120 corresponds to the mobile device located at position X, which assumes that 80% of the received signal power is from cell A and 20% of the received signal power is from cell B. As can be seen from Figure 7, the graph 120 provides discrete signal points for signals received according to 16Q AM, but due to the distribution of possible points due to 20% power from cell B (which transmits 64QAM modulation symbols) A significant increase in noise. Accordingly, graph 122 provides a graph of the signal 値 in the complex plane, -18-201214986 when the receiver is at position Y, and assumes that 60% of the received power is from the cell Α and 40% of the received power is from the cell. Hey. As can be seen from the figure, 'although the signal cluster chart is clustered into a cluster corresponding to each possible 与 of 16QAM symbols, discrete cluster points have been formed according to the 64Q AM modulation architecture. It is understood that if the signal to noise ratio is high enough, a receiver at position Y can detect one of the 64QAM signal points and thus restore the locally inserted data. Accordingly, the right hand graph 124 shows the situation at position Z, which assumes that, for example, only 10% of the signal power is from cell A and 90% of the signal power is from cell B » thus, as shown in graph 124 Clearly, each 64Q AM signal cluster point can be used to detect and recover data, which is generated in the first data pipeline and the local service insertion data pipeline. Therefore, it should be understood that, depending on the location of the receiver, a mobile terminal can recover the locally transmitted data and the data transmitted from the first data pipeline (eg, national broadcast), when located in or near the cell B, and in the cell A. , a receiver will still be able to recover data from the first data pipeline. The effect of the hierarchical modulation provided by the second modulation architecture of the 64Q AM signal and the first modulation architecture 16Q AM will not interrupt the reception of the national broadcast data, when the locally broadcast data is transmitted from an adjacent When the cells are. TDMA Local Service Insertion Some embodiments of the present invention may be further enhanced by allocating local service transmissions between clusters of adjacent cells to achieve transmission of higher order (second) modulation architectures in different cells at different times. The power of the content being transmitted. This technique is illustrated with reference to Figures 9a, 9b and 9c. -19- 201214986 In Figure 9a, a cluster of four cells is shown. These cells are shown with different levels of shading and are individually labeled with Τχ1, Τχ2, Tx3, Tx4β and thus 'Figure 9a shows no clusters of four cells. As will be understood, in addition to receiving data from the first data pipeline (which may be, for example, a national broadcast channel), a local data insertion pipeline incorporating a high-order hierarchical modulation architecture may also be used to provide a regional broadcast, such as As explained above. However, as explained above, when using a second or higher modulation architecture, the effect is noise or interference, which reduces the reception of data from the first communication channel (which is the use of the first or low-order modulation architecture). National Broadcasting) Receiver's signal to noise ratio. More specifically 'for example, if the national broadcast signal from the first data pipeline is modulated using QPSK, and the combined first communication channel and local service insertion channel are modulated to the second or higher order modulation architecture of 16Q AM Then, 16QAM will appear to increase the noise of a receiver attempting to receive an OFDM symbol modulated by the QPSK modulation architecture. In order to reduce the amount of interference caused by the second/high-order modulation architecture (16Q AM) relative to the first/low-order modulation architecture (QPSK), the cells of the broadcast OFDM signal are aggregated as shown in Figure 9a. Furthermore, the transmitters within the four cell clusters shown in Figure 9a alternately broadcast high-order 16QAM modulation signals in a framed manner, which provides data symbols from the first data communication pipeline and its local service insertion pipeline. . This configuration is shown in Figure 9b, in Figure 9b, showing a TDMA frame consisting of four physical layer frames. The physical layer frame is marked with frame 1, frame 2, frame 3 and frame 4. Within each physical layer frame, the OFDM signal conveys data from each PLP. As explained above, the OFDM symbol carrying the data from the first data pipeline and the local service insertion pipeline is also transmitted using, for example, 16QAM, simultaneously with the data transmission of the first data pipeline of QPSK with -20-201214986. . However, in order to reduce the interference caused by the 16QAM modulation, only one of the transmissions Txl, Tx2, Τχ3, Τχ4 within the cluster of four cells is allowed to transmit the OFDM symbol with the high-order 16QAM modulation subcarrier, in the TDMA box. During each physical layer frame period. Therefore, in the physical layer frame 1, only Txl transmits an OFDM symbol having a subcarrier modulated with 16QAM to provide data from the combined first data pipeline and its local service insertion pipeline; and in block 2, only There is a Tx2 transmission with an OFDM symbol of 16Q AM; and thereafter, TX3 is at block 4 and TX4 at block 4. This pattern is then repeated in the next TDMA box. In each case, all other transmitters transmit QPSK modulated OFDM symbols or a cluster for carrying only the first data pipe. Since the transmission of the local service insertion data between each of the four transmitters Txl, Tx2, Tx3, and Tx4 is time-divided, the local data rate is effectively one quarter of the data rate of the first data pipeline. Therefore, each cell line transmits a local service insert to each fourth physical layer box. However, accordingly, because the high-order modulation architecture is transmitted only once from one cell to every four blocks, it is correspondingly reduced by the coverage area of the four cells located in the first/low-order modulation architecture (QPSK) that is desired to receive. The effective interference experienced by the receiver. Thus, in the type of cells shown in Figure 9c, the interference caused by the local service insertion data and the addition of noise to the receiver is distributed throughout the cluster of four cells. As a result, the relative interference or increased noise caused by the insertion of data from the local service is reduced. This can be considered equivalent to -21 - 201214986 reused in frequency in a multi-frequency network. For the example shown in Figures 9a, 9b, 9c, the following table represents the transmission of OFDM symbols in each of the first (1 6QAM) and second (64QAM) modulation architectures:
框1 框2 框3 框4 Txl 64QAM 16QAM 16QAM 16QAM Tx2 16QAM 64QAM 16QAM 16QAM Τχ3 16QAM 16QAM 64QAM 16QAM Τχ4 16QAM 16QAM 16QAM 64QAM 表顯示OFDM符號之調變，當本地服務插入資料係使 用64QAM之第二/較高調變架構而被調變且第—/較低調變 架構爲用以攜載來自第一/國家資料管線之資料符號的 16QAM 時。 如將理解者：將透過四個T DM A框之叢集的本地內容 之傳輸配置於四個基地站的叢集之間的結果可爲減少了本 地內容服務之頻寬的四分之一，假如接收器僅能夠接收來 自一基地站之OFDM攜載信號（其通常將會如此）。將本 地內容配置給各叢集中之基地站的傳輸器可（例如）經由 發信資料管線所提供之發信資料而被提供。 雖然於以上提供之範例中，細胞係聚集成四個之族群 ’但應理解任何數目均可使用。有利地，細胞被群集成四 個之叢集以提供介於下列兩者之間的平衡取捨：能提供給 本地服務插入服務之基頻頻寬的量（位元率）、以及對於 藉由攜載來自第一資料管線和本地服務插入頻道兩者之資 料的高階調變架構之傳輸而接收來自使用低階調變架構之 第一資料管線的資料所造成之信號雜訊比的減少量。如此 -22- 201214986 一來’圖9c中所示之細胞結構可被用以傳輸本地內容於四 個細胞之不同族群的每第四實體層框，及傳輸完全重複之 細胞叢集的配置，以代表頻率再使用之一同等配置。 依據本發明，圖4中所示之基地站內的傳輸器可被調 適成實施上述的TDMA框結構。於一範例中，用以將已調 變的副載波信號形成爲OFDM符號之排程器34和一定框單 元5 8可被配置以依據圖9b中所示之時間分割框來排程 OF DM符號之傳輸。排程器34及定框單元5 8被配置以傳輸 其攜載第一資料管線和本地服務插入管線之資料符號的 OF DM符號，使用如上表中所示之第二調變架構。 結合之本地服務插入與國家廣播信號的等化 現在將參考圖10至15以描述本發明之另一形態。如以 上所解釋，來自本地服務插入頻道之資料與來自國家廣播 頻道之資料係使用高階調變架構（諸如16Q AM)被傳輸， 而來自國家廣播頻道之資料係使用低階調變架構（諸如 QPSK)而被傳輸。可能需要一種行動接收器來在出現 QPSK信號（其僅傳遞來自國家廣播頻道之資料）時檢測 16QAM信號，該行動接收器能夠藉由16QAM調變架構以檢 測連同來自國家廣播頻道之資料被傳遞之本地服務插入資 料。傳遞來自國家廣播頻道和本地廣播頻道之資料的 16QAM調變架構及傳遞國家廣播頻道的QPSK調變架構被 表示於圖3a及3b並描述如上。於以下描述中，依據國家廣 播頻道和本地服務插入頻道以傳遞資料之高階調變架構將 -23- 201214986 被稱爲本地服務插入頻道或資料，而國家廣播頻道將被稱 爲國家廣播頻道、資料或信號。 本發明之一實施例所處理的另一附屬問題是提供一種 接收器，其可等化該接收器上所接收之信號，該信號爲（ 例如）本地服務插入信號（其爲16 QA Μ信號）與國家廣播 信號（其爲QPSK信號）之組合。因此，本發明之另一形 態係有關等化一國家廣播信號與一本地服務插入信號之組 合的信號，其爲16QAM與QPSK信號之組合。 如圖10中所示，一行動接收器Μ被置於大約與其傳輸 本地服務插入信號之基地站112和一傳輸國家廣播信號之 基地站110等距的位置上。因此，由行動接收器Μ所接收之 信號包括本地服務插入信號ί 與國家廣播信號彳Ο 之組合，該本地服務插入信號係卷積（convolved )與本地服務插入基地站112和行動接收器Μ之間的頻道 A而國家廣播信號;係卷積與來自國家廣播基地站110 和行動接收器Μ之頻道。因此，所接收之信號係由下 式所表示（其中「*」代表卷積）^ r(t) = hn(t)*s(t) + hi(t)*[s(t) + d(t)] =s(t)*[hn(t) + hi(t)] + d(t)* hi(t) 接下來，一FFT其中所接收之信號被轉變爲頻率領域 ，形成於FFT之輸出上的信號爲： R(z) = S(z)[Hn(z) + Ηι(ζ)] + D(z)H[(z) 因此，一信號群集可被表示於複數平面以用於圖11a 中所示之國家廣播信號、及圖lib中所示之本地插入信號 ;國家廣播信號爲QPSK (如圖1 la中所示）而本地服務插 -24- 201214986 入信號爲16QAM (如圖ub中所示）。因此，圖1 la之國家 廣播信號提供低階的調變架構，相對於圖1 1 b中所示之 16Q AM的高階調變架構。然而，由圖Ua及lib之群集點所 示的信號之表示並無雜訊，且再者，無任一其他信號之出 現。 圖12a及12b提供複數平面中之信號群集的相應表示， 其中行動接收器Μ係在國家廣播信號和本地服務插入 信號彳⑴兩者皆出現時接收信號且其中頻道回應//«(勹 與並不相等。於圖12a中，如以上所表示之結合信號 的信號群集VZ)爲國家廣播信號與本地廣播信號之結合。 圖12b顯示將所接收之信號R(z)除以(其爲來 自國家廣播信號之基地站110的頻道與本地插入基地站112 之頻道的結合）以產生C(z)。圖12b中之圖表係假設完美 的頻道預估且無雜訊。如可從圖12b看出，將需要僅少量 的雜訊來造成本地廣播信號之特定調變符號的錯誤檢測。 R(z)除以結合之頻道形成一等化的信號C(z): C(Z) = [//» + //,⑺] ~S(Z) + [H„(z)'+Hi(<z))D(z) 然而，無法分別地得知及//心），而因此無法計 算下式： H,{2) [^„(Z)+ //,(7)] 依據本發明，爲了從國家廣播信號復原本地插入信號 -25- 201214986 ，必須分別地決定來自國家基地站1 10之頻道及來自 本地服務插入基地站1 1 2之頻道7/〆^)。得知國家廣播頻道 及本地服務插入頻道，則得以計算D(z)。因此 ，首先檢測使用低階調變架構之國家廣播信號並從所接收 之信號減去該檢測之信號，則能夠得知來自國家廣播基地 站之頻道及本地服務插入信號基地站之頻道///(%>， 以復原本地信號D(z)。因此，依據本發明，術語 被視爲雜訊，且國家廣播資料係 藉由切割以勹而被復原以提供國家廣播信號左⑺之估計。因 此，藉由計算來自國家廣播基地站之頻道及來自本 地服務插入信號基地站之頻道///Γζ)並將這些値之和與國家 廣播信號卷積（藉由頻率領域中之相乘），則得以從所接 收的信號減去此組合以形成與來自本地服務插入基地站之 頻道卷積的本地服務插入信號之估計。 因此，爲了檢測本地服務插入信號，需要下列步驟： 1 .當切割吖幻時，藉由考量rLf/^上，⑺爲雜訊以估 計爲i⑺； 2. 等化器已計算+ 爲組合的頻道； 3. 計算Z)⑺//,⑺以⑺-知)[見⑺+ /f,(z)]:其提供一複數信號 ，如圖13a之複數平面中所示： 4. 假如部分£>⑷係從本地服務插入信號中所提供之額 外引導得知，則"〆衫可被估計以提供成⑷ f R{z)-S{z)[Hn^) + Η,{z)) 5. 外） 6. 可於頻率方向對成(z)執行內插以形成，而因此 -26- 201214986 万 R^-SjzW^ + H^z)} 7.〜 因此，藉由刪除來自本地服務插入基地站之頻道成⑷ ，則形成圖13b中所示之信號群集圖，可從該圖復原本地 服務插入資料D(z)。 如將從以上解釋所理解者，爲了復原本地服務插入資 料乃⑺，必須估計來自本地服務插入基地站之本地服務插 入頻道或⑷，其係不同於來自國家廣播基地站之頻道 於另一實施例中，所計算的乃(Z)可被用以藉由計算下 式而得到i(z)之較佳的估計： R(z) - D(z)Hi(z) = S(z)[Hn(z) + Ηι(ζ)] 接著，各除以並針對S⑺再次切割。此 種f重複可被持續多次以得到對於5⑻之估計的持續增進。 依據本發明，來自本地服務插入基地站之頻道/f〆匀係 藉由將本地服務插入引導符號包括於正傳輸本地服務插入 調變符號之選定的副載波上而被估計。此一配置係顯示於 圖 14a、 14b及14c。 於圖l4a中，提供頻率領域中之OFDM符號的圖示，其 顯示複數副載波，其中部分副載波被接著指定以傳遞依據 國家廣播信號s (t)之資料，以及部分副載波係專屬於顯示 依據習知配置之引導符號Ps。圖14b提供一 OFDM符號之圖 示，其中本地服務插入符號係使用階層式調變架構而被引 入於國家廣播符號之頂部上。然而，爲了估計本地服務插 入符號所被廣播經由的頻道，必須選擇依據本地服務插入 -27- 201214986 而攜載資料之部分副載波，並以已知的符號（其將作用爲 引導符號Pd )來取代這些符號。此一配置係顯示於圖14c 中。因此，應理解本地服務插入引導Pd可被傳輸以取代其 將被傳輸於具有高階調變符號之副載波上的符號，該些高 階調變符號將被配置以攜載本地符號插入資料但卻配置給 這些由已知符號所取代之符號。因此，這些副載波可傳遞 其可作用爲引導Pd之高階調變的已知符號。然而，可理解 的：爲了傳輸本地服務插入引導Pd，必須符合頻率交錯， 其將是本地服務插入資料之習知傳輸所必要的。 如圖4中所示，依據本發明，於各資料片段處理器50 、51之頻率交錯器54的輸出上，包括本地服務插入資料之 資料片段處理器50、51包括一用以插入本地服務插入引導 Pd之區塊182，在產生階層式調變符號（如由圖4中所示之 調變器所形成者）以前。調變器182被配置以依據所使用 之階層式調變架構而將資料符號映射至調變符號上。可選 擇地，當使用多輸入信號輸出（M ISO )技術時，則引導 之進一步處理被執行如由MISO區塊184所示者。接續於 MISO區塊184，引導符號係經由主引導插入單元56而被插 入於分離的引導副載波上，之後，定框單元58結合OFDM 區塊70以形成OFDM符號於頻率領域。 如圖4中所示，於頻率交錯器54之輸出上，在信號插 入資料片段處理器之分支中，在頻率交錯器54後所產生之 本地服務插入資料被饋送至本地引導插入區塊180，其中 本地服務插入之資料符號係藉由以下之任一方式而由引導 -28- 201214986 符號所取代：鑿穿（puncturing )，例如其中將被用以攜 載引導之本地服務插入的調變符號被留空白於資料細胞之 間、或被移動以容納本地服務插入引導。將可理解的：本 地服務插入引導Pd被預先指定而因此可被保留給本地服務 插入引導或者資料可被移動以容納本地服務插入引導》因 此，實質上如圖14c中所表示之配置被產生於QAM調變器 182之輸出處。 圖15提供相應於圖4中所示之槪略方塊圖的槪略方塊 圖，除了圖15提供了其中使用一種多輸入多輸出（ΜΙΜΟ )傳輸技術的範例。然而，ΜΙΜΟ技術之配置的複雜性在 於：本地服務插入引導Pd (其被形成爲階層式調變結構之 部分）需被插入於頻率去交錯器192之前。這是因爲針對 安ΜΙΜΟ技術，在待傳輸之OFDM信號的各版本上之引導係 相對於彼此而調適，且因此每一版本需針對各版本被分別 地形成。此情況適用於國家廣播調變符號以及本地服務插 入符號。因此，無法結合頻率交錯器54之輸出上的本地服 務插入引導。 依據本發明，爲了配合一種配置（其中本地服務插入 引導被形成於頻率交錯器54前之信號中），則本地服務插 入引導係相對於副載波（其係傳遞區塊1 90中之階層式調 變資料）而被配置，並接著被饋送至一頻率去交錯器192 ，其執行由頻率交錯器5 4所執行之交錯的反交錯。因此， 包括本地服務插入引導Pd之引導副載波被配置於其所欲的 位置上，且頻率去交錯器將這些調變符號去交錯，在由本 -29- 201214986 地服務插入資料區塊194供應本地服務插入資料之前。於 Q AM調變器182之輸出處，調變符號被形成且饋送至一 ΜΙΜΟ區塊184»頻率交錯器54接著執行一映射，其爲頻率 去交錯器192所執行之去交錯器映射的反向映射，以致於 頻率交錯器54之輸出處，本地服務插入引導係再次位於本 地服務插入引導之指定副載波上的所欲位置上。因此’ OF DM符號被形成以本地服務插入引導Pd於其所欲的位置 上。國家廣播信號之主引導Ps被接著經由主引導插入區塊 56而加入於相關的副載波位置上，在定框單元58和OFDM 單元70形成OFDM符號前，如習知配置一般。 因此，依據本發明，本地服務插入引導Pd被配置於所 欲的位置上，藉由首先將其設置於其所欲的位置上並接著 使用去交錯器以形成反向交錯，以致當交錯時其被再次配 置於其所欲的位置上。 以下參考圖24以描述一種配置成復原本地服務插入資 料或國家廣播資料之接收架構》 結果 圖16至21提供各種結果，例如，以1/2、3/5、2/3及 3/4等不同前向誤差校正編碼率操作之傳輸器-接收器鏈； 以及16QAM之第一調變架構、64QAM之第二調變架構。圖 16、17、18、19、20及21提供來自細胞A和細胞B之不同功 率比的範例。針對圖1 6，來自細胞A之接收信號的功率之 比例爲99%而來自細胞B爲1 %。介於來自細胞A與B的到達 •30- 201214986 時間之間的相對延遲爲4.375us。針對圖16，來自細胞A之 功率爲8 0%而來自細胞B爲20%，其具有來自細胞B的2.2 μβ之時間延遲。圖17提供來自細胞A之99%功率及來自細 胞B之1%功率，於到達之相對時間的Ops延遲。圖18顯示 來自細胞A之6 0 %功率及來自細胞B之4 0 %功率，於〇 μ s相對 延遲；而圖19顯示來自基地站Α之50 %功率及來自細胞Β之 50%功率，於0μ3相對延遲。最後，圖20顯示於下列一種情 況下之結果：其中1 〇 %功率來自細胞Α而9 0 %來自細胞Β， 而來自細胞A之信號在來自細胞B之信號到達後2.2ns到達 接收器。如可從圖21中之範例看出：信號雜訊比係不足以 解碼3/5、2/3率的碼。所需的SNR應足以解碼64QAM。針 對每一圖表顯示一信號雜訊比値，其將相應於一種情況， 其中用於相同相鄰細胞之傳輸器並不會傳輸本地服務插入 資料於高階調變架構64QAM上（針對本範例）。適當情況 下，某些圖表包括1/2、3/5、2/3及3/4之每一個別編碼率 於1(Γ7之位元誤差率，如表示爲“0”。如各情況中所示，爲 了達到相同位元誤差率値所需之信號雜訊比有所增加。然 而，本技術之性能仍似乎爲可接受的。 接收器 現在將描述一種接收器，其可形成一藉由圖1所示之 網路的任何基地站以接收信號廣播之行動裝置的部分。一 種用以接收圖4中所示之任何傳輸PLP管線的接收器之一範 例架構係提供於圖22中。於圖22中，一接收器天線1 ?4係 -31 - 201214986 檢測攜載OFDM信號之廣播無線電頻率信號，其被饋送至 —無線電頻率調諧器1 75以便執行時間領域基頻信號之解 調及類比至數位轉換。一框復原處理器158復原分時多工 實體層框邊界及OFDM符號邊界，並將每一實體層框之每 一符號饋送至OFDM檢測器150。OFDM檢測器150接著復原 來自時間領域中之OFDM符號的國家廣播資料和本地服務 插入資料。復原的國家廣播資料和本地服務插入資料被接 著饋送至去排程器134，其將每一這些符號劃分爲個別多 工的PLP處理管線。因此，去排程器係將圖4中所示之排程 器134的多工反轉以形成複數資料串，其被個別地饋送至 PLP處理管線129、130、136。一典型的接收器將僅具有一 單一PLP處理管線，因爲各PLP可攜載一完整的廣播服務 且此PLP處理管線係處理來自任何國家廣播PLP或任何本 地服務插入PLP之資料。形成圖22中所示之PLP處理管線 的部分之處理元件係顯示於圖23。 於圖23中，第一範例PLP處理管線130被顯示爲包括一 QAM解調器144、一去交錯器142及一前向誤差校正解碼器 140，其被配置以實質上將圖4之QAM調變器44、交錯器42 及FEC編碼器40的操作反轉。可選擇地，PLP處理管線130 亦可包括MIS 0/ΜΙΜ0解碼器46，用以執行多輸入多輸出或 多輸入信號輸出處理。因此，於操作時，調變符號被接收 於一輸入200並饋送至MISO/MIMO處理器146，其角色係用 以解碼傳輸器上所使用之空間時間碼，藉此產生調變符號 之一串流以成爲一信號符號串，其被接著饋送至Q AM解調 -32- 201214986 器144。QAM解調器係檢測所使用之QAM調變架構中的群 集點之一，並針對各檢測的點復原一相應於該點之資料字 元。因此，QAM解調器144之輸出爲一資料符號串，其被 饋送至去交錯器142以將來自複數OFDM符號或來自一 OFDM符號內之資料串去交錯。 因爲資料符號已被編碼於圖4所示之傳輸器中，例如 ，使用低密度同位檢査碼，所以該些符號係由FEC解碼器 140所解碼以形成PLP之基頻資料串於輸出202上。 依據本發明，於某些實施例中，去排程器150被配置 以依據上述基地站之叢集而供應TDM A框來復原OFDM符號 ’其已利用第二調變架構而被調變且被傳輸於實體層框之 ~上。因此，依據配置給細胞叢集之信號傳輸，接收器對 其具有依據第二調變架構而調變之副載波的OFDM符號之 復原計時，依據基地站中由傳輸器所供應之框時序。有關 哪些實體層框攜載該既定PLP之資訊被攜載於發信PLP中 ，該發信PLP爲任何攜載PLP之酬載（payload)前由接收 器所首先接收並解碼者。 等化接收之單頻信號 圖24提供如圖22中所示之OFDM檢測器150的槪略方塊 圖之表示。此可被用於SISO、MISO或ΜΙΜΟ架構。於圖24 中，一快速傅立葉轉換FFT區塊290將來自時間領域之接收 信號轉換爲頻率領域。一國家廣播信號等化器292接著接 收頻率領域OFDM符號並形成結合之本地服務插入頻道和 -33 - 201214986 國家廣播頻道以及接收之國家廣播資料的估計。形成單頻 網路等化器292之區塊係顯示於一擴展區域294中。如擴展 區域294中所示，單頻網路等化器包含一引導分離器296， 其係從接收之頻率領域信號分離引導。頻率領域信號被饋 送於引導分離器296之一輸出298上而至一分割器單元300 。從引導分離器296之第二輸出302，引導副載波被解調、 被一時間內插單元3 04內插於時間、以及被一頻率內插單 元308內插於頻率，以於一輸入310形成結合之國家廣播頻 道和本地服務插入頻道之估計至分割器300，以致分割器 之輸出形成一代表國家廣播信號S(z) 312之信號。 如接收器鏈中所示，一去映射器314接著藉由切割以 真實及虛擬平面發信之調變而解讀所接收之調變信號，來 檢測國家廣播信號之估計S⑺。代表國家廣播信號S(z) 312 之信號被接著饋送至一頻率去交錯器31 6及接著至一去排 程器134 (如以上所解釋）以供國家廣播信號之一般資料 復原。 於接收器架構之下部分上，所測得之結合的本地服務 插入頻道和國家廣播頻道被饋送於一輸出311上而至一本 地等化器320之第一輸入。 國家廣播信號之估計左⑺3 15被饋送至一多工器322， 其係在一第二輸入上接收結合的本地服務插入頻道和國家 廣播頻道之估計310。一減法單元3 24接著從接收的信號減 去國家廣播符號的估計乘以結合的本地服務插入和國家廣 播頻道之乘積，以形成其被饋送至本地等化器320之本地 -34- 201214986 服務插入符號的估計。本地等化器320之內部結構係類似 於國家廣播信號等化器之內部結構。於本地服務插入引導 分離器326之輸出處，引導信號係於一輸出3 2 8上被饋送至 一引導解調器330及接著至一時間內插單元332，其後接著 —頻率內插單元334，該頻率內插單元33 4係形成該些本地 服務插入符號已通過之頻道的估計。本地服務插入資料之 估計係於一輸入336上被饋送至分割器338，其係於來自引 導分離器3 26之另一輸入340上接收本地服務插入符號，並 於一輸出342上形成本地服務插入資料符號之估計。一去 映射器344及頻率去交錯器3M接著形成代表其被饋送至去 排程器134之本地插入資料的資料之估計。之後，本地插 入資料之資料復原係相當於有關圖23中所示之資料管線而 顯示的資料復原。 應理解者：本發明之另一形態係提供國家廣播資料之 第一估計，其接著根據本地服務插入符號之判斷而被精化 ，以形成國家廣播符號之進一步精化的估計，其可被用以 進一步計算本地服務插入符號之精化的估計。因此，可形 成一種渦輪解調之形式的循環回饋配置，以提供對於接收 信號之估計的進一步增進。 操作之槪述 綜言之，由圖25中所示之流程圖來說明圖24中所示之 用以從本地服務插入符號復原本地資料的接收器之操作， 其被槪述如下： -35- 201214986 S2 :國家廣播符號之估計i⑺係藉由將 D(<z) [Ηα(ζ) + Η,(ζ)] 視爲雜訊並在真實及虛擬平面周圍切割復原的信號以形成 國家廣播資料之估計而被形成。 S4 :使用主副載波Ps以形成傳輸來自國家廣播基地站 和本地服務插入基地站之頻道的結合頻道之估計，來計算 —代表與結合之國家廣播和本地服務插入頻道卷積之再生 的國家廣播信號之項的估計f(z)[//„(Z) + //,(Z)]。 S6:藉由從接收的信號減去從步驟S4產生的項，來形 成卷稂與本地頻道之本地服務插入符號的估計 Z)⑷A⑺左⑺[//n(2) + 7/,⑺])。 S8:使用本地服務插入引導以判斷本地服務插入已從 基地站通過至接收器所經過之頻道的估計成⑺。' S 1 0 :接著從藉由將復原之項除以本地頻道之估計所 產生的符號來估計本地服務插入資料 H,(z) 可對上述本發明進行各種修改而不背離如後附申請專 利範圍中所界定之本發明的精神。例如，對接收器進行適 當的調整，則可使用除了上述那些以外的其他調變架構。 再者，可如上所述地重複調變程序數次以增進所接收之符 號的估計。再者，接收器可被用於各種系統，其係利用除 了那些依據DVB手持標準所界定者以外的OFDM調變。 本申請案之內容主張UK專利申請案GB 1 003 23 7.3及 GB 1 01 7564.4之優先權，其內容被倂入於此以供參考。 -36- 201214986 【圖式簡單說明】 現在將參考後附圖形僅以範例方式描述本發明之實施 例，其中類似的部件係使用相同的數字指定來參考，而其 中： 圖1係複數基地站之一槪略表示，該些複數基地站形 成一單頻網路以廣播（例如）可形成手持式DVB TV廣播 系統之部分的視頻信號； 圖2係依據先前技術之一範例傳輸器的槪略方塊圖； 圖3a係一複數平面之槪略表示，其提供QPSK之第一 調變架構的信號群集點之圖示；圖3b係一複數平面之槪略 表示，其提供16QAM之第二調變架構的信號群集點之圖示 ，依據先前技術； 圖4係一種用於圖1所示之一或更多基地站中的傳輸器 之部分的槪略方塊圖，依據支援SISO或MISO之本發明； 圖5係形成圖4中所示之傳輸器的部分之一範例調變器 的槪略方塊圖； 圖6係形成兩個細胞A及B之兩相鄰基地站的圖示’該 兩個細胞A及B係個別地使用1 6Q AM之第一調變架構及 64QAM之第二調變架構； 圖7係一槪略表示，其顯示對於如由—行動裝置在圖6 的兩基地站A與B間之三個不同位置X、Y、Z上所接收的群 集點之效果： 圖8係一疊置在64QAM之第二調變架構上的16QAM之 第一調變架構的複數平面中之群集點的圖示； -37- 201214986 圖9a係由依據本發明之四個基地站所服務的四個細胞 之叢集的圖示；圖9b係頻率相對於時間之圖表的圖形表示 ，其提供一分時多工框結構的示圖；及圖9 c係依據本發明 之細胞叢集的型態之圖示； 圖10係形成兩個細胞A及B之兩相鄰基地站的圖示，該 兩個細胞A及B係個別地使用16QAM之第一調變架構及 64Q AM之第二調變架構；並使用一行動接收器，其可被配 置以於來自第一調變架構及第二調變架構兩者之信號均存 在時復原本地服務插入資料，其中來自細胞B之信號係傳 輸一頻道脈衝回應hn(t)而來自細胞A之信號係傳輸一頻道 脈衝回應h i (t); 圖1 la係一複數平面之槪略表示，其提供QPSK之第一 調變架構的信號群集點之圖示；及圖1 lb係一複數平面之 槪略表示，其提供16Q AM之第二調變架構的信號群集點之 圖示，其中接收並無雜訊且爲完美的頻道預估； 圖12a係一複數平面之槪略表示，其提供QPSK之第一 調變架構的信號群集點之圖示，當存在第二調變架構的情 況下接收時，但來自各細胞之信號係傳輸通過不同頻道脈 衝回應之頻道；及圖12b提供在使用一種具有完美頻道估 計之習知等化器來執行等化後的相同信號之相應表示； 圖13a係一複數平面之槪略表示，其提供在減去 SesJzHCHKzhHJz))後的信號群集點之圖示；及圖13b係 將圖13a中所示之信號除以HKz)所得的結果，其係假設其 中本地服務插入頻道HKz)爲確實已知的完美頻道估計； -38- 201214986 圖14a係攜載國家廣播信號之OFDM符號的窄頻帶載波 之圖示；圖14b係攜載國家廣播信號及本地服務插入信號 之OFDM符號的窄頻帶載波之圖示；及圖14c係攜載本地服 務插入信號之OFDM符號的窄頻帶載波之圖示，但依據本 發明而調適以包括本地引導（pilots ); 圖15係使用於依據本發明之一或更多基地站中的傳輸 器之槪略方塊圖，其支援ΜΙΜΟ ; 圖1 6係針對（例如）低密度同位檢查（LDPC )編碼 的OFDM傳輸器一接收器鏈之信號雜訊比的位元錯誤率之 圖表，以：1/2、3/5、2/3和3/4之錯誤校正編碼率； 16QAM之第一調變架構64QAM之第二調變架構；及其中 接收器被視爲位於細胞A之覆蓋區域內並接收具有來自基 地站A 99%及來自基地站B 1%之信號功率的OFDM符號， 其來自B之信號係在來自A之信號後4.375us到達接收器， 如圖6中之範例圖形所示者； 圖17係針對（例如）LDPC編碼的OFDM傳輸器一接收 器鏈之信號雜訊比的位元錯誤率之圖表，以：1/2、3/5、 2/3和3/4之錯誤校正編碼率；16QAM之第一調變架構； 64Q AM之第二調變架構；及其中接收器被視爲位於細胞A 之覆蓋區域內並接收具有來自基地站A 80%及來自基地站 B 2 0%之信號功率的OFDM符號，其來自B之信號係在來自 基地站A之信號後2.2μ5到達接收器，如圖6中之範例圖形 所示者； 圖18係針對（例如）LDPC編碼的OFDM傳輸器一接收 -39- 201214986 器鏈之信號雜訊比的位元錯誤率之圖表，以：1/2、3/5、 2/3和3/4之錯誤校正編碼率；16QAM之第一調變架構； 64Q AM之第二調變架構：及其中接收器被視爲位於細胞A 之覆蓋區域內並接收具有來自基地站A 99%及來自基地站 B 1%之信號功率的OFDM符號，其具有零延遲於來自兩細 胞的信號到達時間之間，如圖6中之範例圖形所示者； 圖19係針對（例如）LDPC編碼的OFDM傳輸器一接收 器鏈之信號雜訊比的位元錯誤率之圖表，以：1/2、3/5、 2/3和3/4之錯誤校正編碼率；16QAM之第一調變架構； 04QAM之第二調變架構；及其中接收器被視爲位於細胞Λ 之覆蓋區域內並接收具有來自基地站A 60 %及來自基地站 B 40%之信號功率的OFDM符號，其具有零延遲於來自兩細 胞的信號到達時間之間，如圖6中之範例圖形所示者； 圖2〇係針對（例如）LDPC編碼的OFDM傳輸器一接收 器鏈之信號雜訊比的位元錯誤率之圖表，以：1/2、3/5、 2/3和3/4之錯誤校正編碼率：16QAM之第一調變架構； 64Q AM之第二調變架構：及其中接收器被視爲位於細胞A 之覆蓋區域內並接收具有來自基地站A 50%及來自基地站 B 5 0%之信號功率的OFDM符號，其具有零延遲於來自兩細 胞的信號到達時間之間，如圖6中之範例圖形所示者； 圖21係針對（例如）LDPC編碼的OFDM傳輸器一接收 器鏈之信號雜訊比的位元錯誤率之圖表，以：1/2、3/5和 2/3之錯誤校正編碼率；16QAM之第一調變架構；64QAM 之第二調變架構；及其中接收器被視爲位於細胞B之覆蓋 -40- 201214986 區域內並接收具有來自基地站A 10%及來自基地站B 90% 之信號功率的OFDM符號，其來自A之信號係在來自基地站 B之信號後2·2μ3到達接收器，如圖6中之範例圖形所示者 ， 圖22係依據本發明之一實施例的接收器之槪略方塊圖 圖23係出現在圖22中之接收器中的實體層管線（PLP )之方塊圖； 圖24係一方塊圖，其說明依據本發明之另一範例實施 例而調適的接收器；及 圖25係一流程圖，其說明用以等化一單頻信號所需的 程序之範例操作，其包括來自第一和第二調變架構之要件 【主要元件符號說明】 1 :傳輸天線 2 :邊界 8 :調變器 3 0 :資料管線 34 :排程器 36:發信資料處理管線 3 8 :輸入 40 :前向錯誤校正編碼器 42 :交錯器 -41 - 201214986 44 :調變器 50、51、52:資料片處理單元 54 :頻率交錯器 56 :引導產生器 58 :定框單元 70 : OFDM調變器 72 : RF調變器 7 4 :天線 80:本地服務插入資料片處理器 8 2 :第一輸入 84 :第二輸入 90 :資料字元形成器 92 :資料字元形成器 94 :符號選擇器 94.1 :輸出 96 :符號選擇器 96.1 :輸出 98 :開關單元 100 :控制輸入 102 :輸出頻道 1 1 0 :基地站 1 1 2 :基地站 129、130、136 ： PLP處理管線 134 :去排程器 -42- 201214986 140 :前向誤差校正解碼器 142 :去交錯器 144 : QAM解調器 146: MISO/MIMO處理器 150 : OFDM檢測器 1 5 8 :框復原處理器 174 :接收器天線 175 :無線電頻率調諧器 180 :本地引導產生器 182 :調變器 184: MISO處理單元 1 90 :區塊 192 :頻率去交錯器 194 :本地服務插入資料區塊 200 :輸入 202 :輸出 290:快速傅立葉轉換FFT區塊 292 :國家廣播信號等化器 2 9 4 :擴展區域 296 :引導分離器 298 :輸出 300 :分割器單元 3 02 :第二輸出 3 04 :時間內插單元 -43- 201214986 3 08 :頻率內插單元 310 :輸入 31 1 :輸出 312 :國家廣播信號S(z) 3 1 4 :去映射器 315:國家廣播信號之估計 316 :頻率去交錯器 320 :本地等化器 3 2 2 :多工器 324 :減法單元 326 :本地服務插入引導分離器 328 :輸出 3 3 0 :引導解調器 33 2 :時間內插單元 334:頻率內插單元 336 :輸入 3 3 8 :分割器 3 40 :輸入 342 :輸出 344 :去映射器 346 :頻率去交錯器 -44-Box 1 Box 2 Box 3 Box 4 Txl 64QAM 16QAM 16QAM 16QAM Tx2 16QAM 64QAM 16QAM 16QAM Τχ 3 16QAM 16QAM 64QAM 16QAM Τχ 4 16QAM 16QAM 16QAM 64QAM The table shows the modulation of the OFDM symbol, when the local service insertion data system uses the second / higher tone of 64QAM The architecture is modified and the first/lower modulation architecture is used to carry 16QAM from the data symbols of the first/national data pipeline. As will be understood, the result of configuring the transmission of local content through the cluster of four T DM A boxes between the clusters of the four base stations may be to reduce the bandwidth of the local content service by a quarter, if received The device is only capable of receiving OFDM carried signals from a base station (which would normally be the case). The transmitter that configures the local content to the base stations in each cluster can be provided, for example, via the signaling material provided by the signaling data pipeline. Although in the examples provided above, the cell lines are clustered into four ethnic groups', it should be understood that any number can be used. Advantageously, the cells are clustered into four clusters to provide a balance between the following: the amount of baseband bandwidth (bit rate) that can be provided to the local service insertion service, and The transmission of the high-order modulation architecture of the data of both the first data pipeline and the local service insertion channel receives the reduction in the signal-to-noise ratio caused by the data from the first data pipeline using the low-order modulation architecture. Thus -22-201214986 a cell structure as shown in Figure 9c can be used to transmit local content to each of the fourth physical layer frames of different populations of four cells, and to transmit a completely repetitive arrangement of cell clusters to represent The frequency is reused in one of the same configurations. In accordance with the present invention, the transmitters in the base station shown in Figure 4 can be adapted to implement the TDMA frame structure described above. In an example, the scheduler 34 and the fixed frame unit 58 for forming the modulated subcarrier signal into an OFDM symbol can be configured to schedule the OF DM symbol according to the time division frame shown in FIG. 9b. Transmission. The scheduler 34 and the framing unit 58 are configured to transmit the OF DM symbols carrying the data symbols of the first data pipeline and the local service insertion pipeline, using the second modulation architecture as shown in the above table. Combination of Local Service Insertion and National Broadcast Signal Equalization A further aspect of the present invention will now be described with reference to Figs. As explained above, the information from the local service plug-in channel and the data from the national broadcast channel are transmitted using a high-order modulation architecture (such as 16Q AM), while the data from the national broadcast channel uses a low-order modulation architecture (such as QPSK). ) is transferred. A mobile receiver may be needed to detect the 16QAM signal when a QPSK signal (which only passes data from the national broadcast channel) is detected, the mobile receiver being capable of detecting the data transmitted along with the data from the national broadcast channel by means of a 16QAM modulation architecture. Local service inserts data. The 16QAM modulation architecture that conveys material from national broadcast channels and local broadcast channels and the QPSK modulation architecture that delivers national broadcast channels are shown in Figures 3a and 3b and described above. In the following description, a high-order modulation architecture that inserts channels according to national broadcast channels and local services to deliver data will be referred to as a local service insertion channel or material, while the national broadcast channel will be referred to as a national broadcast channel, data. Or signal. Another subsidiary problem addressed by an embodiment of the present invention is to provide a receiver that can equalize the received signal on the receiver, such as a local service insertion signal (which is a 16 QA Μ signal). Combined with a national broadcast signal, which is a QPSK signal. Thus, another aspect of the present invention relates to a signal that combines a combination of a national broadcast signal and a local service insertion signal, which is a combination of 16QAM and QPSK signals. As shown in Fig. 10, a mobile receiver Μ is placed approximately equidistant from the base station 112 that transmits the local service insertion signal and a base station 110 that transmits the national broadcast signal. Thus, the signal received by the mobile receiver 包括 includes a combination of a local service insertion signal ί and a national broadcast signal conv convolved with the local service insertion base station 112 and the mobile receiver. Inter-channel A and national broadcast signals; convolution with channels from national broadcast base stations 110 and mobile receivers. Therefore, the received signal is represented by the following equation (where "*" stands for convolution) ^ r(t) = hn(t)*s(t) + hi(t)*[s(t) + d( t)] = s(t)*[hn(t) + hi(t)] + d(t)* hi(t) Next, the signal received by an FFT is converted into a frequency domain, which is formed in the FFT. The signal on the output is: R(z) = S(z)[Hn(z) + Ηι(ζ)] + D(z)H[(z) Therefore, a signal cluster can be represented in the complex plane for The national broadcast signal shown in Figure 11a, and the local insertion signal shown in Figure lib; the national broadcast signal is QPSK (as shown in Figure 1 la) and the local service plug-in-24-201214986 incoming signal is 16QAM (Figure Shown in ub). Therefore, the national broadcast signal of Figure 1 la provides a low-order modulation architecture, relative to the 16Q AM high-order modulation architecture shown in Figure 11.b. However, there is no noise in the representation of the signals represented by the cluster points of Figures Ua and lib, and further, no other signals are present. Figures 12a and 12b provide respective representations of signal clusters in a complex plane, wherein the mobile receiver receives signals when both the national broadcast signal and the local service insertion signal 彳(1) are present and wherein the channel responds ///(勹和和Not equal. In Figure 12a, the signal cluster VZ) of the combined signal as indicated above is a combination of a national broadcast signal and a local broadcast signal. Figure 12b shows the received signal R(z) divided by (which is the combination of the channel of the base station 110 from the national broadcast signal and the channel of the local insertion base station 112) to produce C(z). The chart in Figure 12b assumes a perfect channel estimate and no noise. As can be seen from Figure 12b, only a small amount of noise will be required to cause false detection of the particular modulation symbol of the local broadcast signal. R(z) divided by the combined channel to form an equalized signal C(z): C(Z) = [//» + //, (7)] ~S(Z) + [H„(z)'+Hi (<z))D(z) However, it is not possible to separately know and//heart), and therefore the following formula cannot be calculated: H, {2) [^„(Z)+ //,(7)] In order to restore the local insertion signal -2514 2012986 from the national broadcast signal, the channel from the national base station 1 10 and the channel 7/〆^ from the local service insertion base station 1 1 2 must be separately determined. It is known that the national broadcast channel and the local service are inserted into the channel, and D(z) can be calculated. Therefore, by first detecting the national broadcast signal using the low-order modulation architecture and subtracting the detected signal from the received signal, it is possible to know the channel from the national broadcast base station and the local service insertion signal base station channel /// (%>, to recover the local signal D(z). Thus, in accordance with the present invention, the term is considered to be a noise, and the national broadcast data is restored by cutting to provide an estimate of the left (7) of the national broadcast signal. Therefore, by calculating the channel from the national broadcasting base station and the channel from the local service insertion signal base station///Γζ and convolving these sums with the national broadcast signal (by multiplication in the frequency domain), This combination is then subtracted from the received signal to form an estimate of the local service insertion signal convolved with the channel from the local service insertion base station. Therefore, in order to detect the local service insertion signal, the following steps are required: 1. When cutting the illusion, by considering rLf/^, (7) is the noise to estimate i(7); 2. The equalizer has calculated + is the combined channel 3. Calculate Z) (7) / /, (7) to (7) - know [see (7) + / f, (z)]: it provides a complex signal, as shown in the complex plane of Figure 13a: 4. If part of the £ > (4) is obtained from the additional guidance provided in the local service insertion signal, then the "shirt can be estimated to provide (4) f R{z)-S{z)[Hn^) + Η, {z)) 5. External) 6. Interpolation can be performed in the frequency direction to form (z), and thus -26- 201214986 million R^-SjzW^ + H^z)} 7.~ Therefore, by deleting the local service The channel inserted into the base station is (4), and the signal cluster diagram shown in Fig. 13b is formed, from which the local service insertion data D(z) can be restored. As will be understood from the above explanation, in order to restore the local service insertion data (7), it is necessary to estimate the local service insertion channel from the local service insertion base station or (4), which is different from the channel from the national broadcast base station in another embodiment. Among them, the calculated (Z) can be used to obtain a better estimate of i(z) by calculating the following formula: R(z) - D(z)Hi(z) = S(z)[Hn (z) + Ηι(ζ)] Next, each is divided and cut again for S(7). This f-repetition can be continued multiple times to obtain a continuous improvement in the estimate of 5(8). In accordance with the present invention, the channel from the local service insertion base station is estimated by including the local service insertion pilot symbol on the selected subcarrier of the transmission local service insertion modulation symbol. This configuration is shown in Figures 14a, 14b and 14c. In FIG. 14a, an illustration of an OFDM symbol in the frequency domain is provided, which displays a plurality of subcarriers, wherein a portion of the subcarriers are subsequently designated to convey data according to the national broadcast signal s(t), and a portion of the subcarriers are dedicated to the display. The pilot symbol Ps is configured according to the conventional knowledge. Figure 14b provides an illustration of an OFDM symbol in which a local service insertion symbol is introduced on top of a national broadcast symbol using a hierarchical modulation architecture. However, in order to estimate the channel through which the local service insertion symbol is broadcast, it is necessary to select a part of the subcarrier carrying the data according to the local service insertion -27-201214986, and with the known symbol (which will act as the pilot symbol Pd) Replace these symbols. This configuration is shown in Figure 14c. Therefore, it should be understood that the local service insertion pilot Pd can be transmitted instead of the symbols it will be transmitted on the subcarriers with higher order modulation symbols that will be configured to carry the local symbol insertion data but configured Give these symbols replaced by known symbols. Thus, these subcarriers can pass known symbols that can act to direct high order modulation of Pd. However, it will be appreciated that in order to transmit the local service insertion pilot Pd, frequency interleaving must be met, which would be necessary for the conventional transmission of local service insertion data. As shown in FIG. 4, in accordance with the present invention, on the output of the frequency interleaver 54 of each of the material fragment processors 50, 51, the data fragment processor 50, 51 including the local service insertion data includes a plug for insertion of a local service. The block 182 of Pd is directed before the hierarchical modulation symbol (as formed by the modulator shown in Figure 4) is generated. The modulator 182 is configured to map the data symbols onto the modulation symbols in accordance with the hierarchical modulation architecture used. Alternatively, when multiple input signal output (MISO) techniques are used, then further processing of the bootstrap is performed as indicated by MISO block 184. Following the MISO block 184, the pilot symbols are inserted onto the separate pilot subcarriers via the primary pilot insertion unit 56, after which the framing unit 58 combines the OFDM blocks 70 to form OFDM symbols in the frequency domain. As shown in FIG. 4, on the output of the frequency interleaver 54, in the branch of the signal insertion data segment processor, the local service insertion data generated after the frequency interleaver 54 is fed to the local boot insertion block 180, The data symbol inserted by the local service is replaced by the symbol -28-201214986 by any of the following methods: puncturing, for example, a modulation symbol in which the local service to be used to carry the guidance is inserted. Leave blank between data cells, or be moved to accommodate local service insertion boots. It will be understood that the local service insertion guide Pd is pre-specified and thus can be reserved for the local service insertion guide or the material can be moved to accommodate the local service insertion guide. Thus, a configuration substantially as shown in Figure 14c is generated The output of the QAM modulator 182. Figure 15 provides a schematic block diagram corresponding to the block diagram shown in Figure 4, except that Figure 15 provides an example in which a multiple input multiple output (") transmission technique is used. However, the complexity of the configuration of the technique is that the local service insertion pilot Pd (which is formed as part of the hierarchical modulation structure) needs to be inserted before the frequency deinterleaver 192. This is because for the ampoule technology, the guidance on each version of the OFDM signal to be transmitted is adapted relative to each other, and thus each version needs to be formed separately for each version. This applies to national broadcast modulation symbols as well as local service insertion symbols. Therefore, the local service insertion guide on the output of the frequency interleaver 54 cannot be combined. In accordance with the present invention, in order to accommodate a configuration in which a local service insertion guide is formed in a signal preceding the frequency interleaver 54, the local service insertion guidance is relative to the subcarrier (the hierarchical modulation in the transmission block 1 90) The data is configured and then fed to a frequency deinterleaver 192 that performs the interleaved deinterlacing performed by the frequency interleaver 54. Therefore, the pilot subcarrier including the local service insertion pilot Pd is placed at its desired location, and the frequency deinterleaver deinterleaves the modulation symbols, and is locally supplied by the service insertion data block 194 by this -29-201214986. Before the service inserts the data. At the output of the Q AM modulator 182, the modulation symbols are formed and fed to a block 184. The frequency interleaver 54 then performs a mapping which is the inverse of the deinterleaver mapping performed by the frequency deinterleaver 192. To the mapping, so that the output of the frequency interleaver 54, the local service insertion guidance is again located at the desired location on the designated subcarrier of the local service insertion guide. Thus the 'OF DM symbol is formed with the local service insertion leading Pd at its desired location. The primary pilot Ps of the national broadcast signal is then added to the associated subcarrier position via the primary pilot insertion block 56, before the framing unit 58 and the OFDM unit 70 form the OFDM symbol, as is conventionally configured. Thus, in accordance with the present invention, the local service insertion guide Pd is placed at the desired location by first placing it at its desired location and then using a deinterleaver to form an inverse interlace so that when interleaved It is again placed in its desired position. Referring now to Figure 24, a receiving architecture configured to restore local service insertion data or national broadcast data will be described. Results Figures 16 through 21 provide various results, for example, 1/2, 3/5, 2/3, 3/4, etc. Different forward error correction coding rate operation transmitter-receiver chain; and 16QAM first modulation architecture, 64QAM second modulation architecture. Figures 16, 17, 18, 19, 20 and 21 provide examples of different power ratios from Cell A and Cell B. For Figure 16, the ratio of the power of the received signal from Cell A is 99% and that of Cell B is 1%. The relative delay between arrivals from cells A and B • 30-201214986 was 4.375us. For Figure 16, the power from cell A was 80% and from cell B was 20% with a time delay of 2.2 μβ from cell B. Figure 17 provides an Ops delay from the 99% power of Cell A and the 1% power from Cell B at the relative time of arrival. Figure 18 shows 60% power from cell A and 40% power from cell B, relative delay in 〇μs; and Figure 19 shows 50% power from the base station and 50% power from cell ,, 0μ3 relative delay. Finally, Figure 20 shows the results in one of the following cases: where 1 〇 % power comes from cell Α and 90% comes from cell Β, and the signal from cell A arrives at the receiver 2.2 ns after the signal from cell B arrives. As can be seen from the example in Figure 21, the signal to noise ratio is not sufficient to decode the 3/5, 2/3 rate code. The required SNR should be sufficient to decode 64QAM. A signal noise ratio is displayed for each graph, which will correspond to a situation where the transmitter for the same adjacent cell does not transmit the local service insertion data on the high order modulation architecture 64QAM (for this example). Where appropriate, some charts include each of the 1/2, 3/5, 2/3, and 3/4 encoding rates at 1 (Γ7 bit error rate, as expressed as "0". As in each case As shown, the signal to noise ratio required to achieve the same bit error rate is increased. However, the performance of the present technique still appears to be acceptable. The receiver will now describe a receiver that can be formed by Any base station of the network shown in Figure 1 is part of a mobile device that receives signal broadcasts. An exemplary architecture for receiving one of the transmit PLP pipelines shown in Figure 4 is provided in Figure 22. In Fig. 22, a receiver antenna 1 - 4 is -31 - 201214986 detects a broadcast radio frequency signal carrying an OFDM signal, which is fed to a radio frequency tuner 1 75 for performing demodulation and analogy of the time domain baseband signal. To digital conversion, a frame restoration processor 158 restores the time division multiplex entity layer frame boundary and the OFDM symbol boundary and feeds each symbol of each physical layer frame to the OFDM detector 150. The OFDM detector 150 then recovers from time. OFDM symbols in the field The home broadcast material and the local service insert data. The restored national broadcast material and local service insert data are then fed to a de-scheduler 134, which divides each of these symbols into individual multiplexed PLP processing pipelines. The multiplex of the scheduler 134 shown in Figure 4 is inverted to form a complex data string that is individually fed to the PLP processing pipelines 129, 130, 136. A typical receiver will have only a single PLP. The pipeline is processed because each PLP can carry a complete broadcast service and this PLP processing pipeline processes the data from any national broadcast PLP or any local service plugged PLP. The processing elements that form part of the PLP processing pipeline shown in Figure 22 The system is shown in Figure 23. In Figure 23, a first exemplary PLP processing pipeline 130 is shown to include a QAM demodulator 144, a deinterleaver 142, and a forward error correction decoder 140 that are configured to substantially The operation of the QAM modulator 44, the interleaver 42 and the FEC encoder 40 of FIG. 4 is reversed. Alternatively, the PLP processing pipeline 130 may also include a MIS 0/ΜΙΜ0 decoder 46 for performing multiple input multiple output orThe input signal is output processed. Therefore, in operation, the modulation symbol is received at an input 200 and fed to the MISO/MIMO processor 146, the role of which is to decode the spatial time code used on the transmitter, thereby generating a tone One of the variable symbols is streamed to become a string of signal symbols, which is then fed to a Q AM demodulation-32-201214986 144. The QAM demodulator detects one of the cluster points in the QAM modulation architecture used, and A data word corresponding to the point is restored for each detected point. Thus, the output of QAM demodulator 144 is a data symbol string that is fed to deinterleaver 142 to derive from or from an OFDM symbol. The data string inside is deinterlaced. Since the data symbols have been encoded in the transmitter shown in Figure 4, e.g., using low density parity check codes, the symbols are decoded by FEC decoder 140 to form the baseband data string of the PLP on output 202. In accordance with the present invention, in some embodiments, the despatcher 150 is configured to supply a TDM A block in accordance with the cluster of base stations described above to recover the OFDM symbol 'which has been modulated and transmitted using the second modulation architecture On the physical layer frame ~. Therefore, depending on the signal transmission configured for the cluster of cells, the receiver counts the OFDM symbols of the subcarriers that are modulated according to the second modulation architecture, according to the frame timing supplied by the transmitter in the base station. Information about which physical layer frames carry the intended PLP is carried in the transmitting PLP, which is first received and decoded by the receiver before any payload carrying the PLP. Equalizing the Received Single Frequency Signal FIG. 24 provides a schematic representation of a block diagram of the OFDM detector 150 as shown in FIG. This can be used for SISO, MISO or ΜΙΜΟ architecture. In Figure 24, a fast Fourier transform FFT block 290 converts the received signal from the time domain into a frequency domain. A national broadcast signal equalizer 292 then receives the frequency domain OFDM symbols and forms a combined local service insertion channel and an estimate of the national broadcast channel received and the received national broadcast material. The block forming the single frequency network equalizer 292 is shown in an extended area 294. As shown in extension area 294, the single frequency network equalizer includes a pilot splitter 296 that separates and directs signals from the received frequency domain. The frequency domain signal is fed to one of the outputs 298 of the pilot splitter 296 to a splitter unit 300. From the second output 302 of the pilot splitter 296, the pilot subcarrier is demodulated, interpolated by a time interpolating unit 304, and interpolated to a frequency by a frequency interpolating unit 308 for forming an input 310. The combination of the national broadcast channel and the local service insertion channel is estimated to the splitter 300 such that the output of the splitter forms a signal representative of the national broadcast signal S(z) 312. As shown in the receiver chain, a demapper 314 then interprets the received modulated signal by modulating the modulation of the real and virtual plane signaling to detect the estimate S(7) of the national broadcast signal. The signal representative of the national broadcast signal S(z) 312 is then fed to a frequency deinterleaver 31 6 and then to a de-router 134 (as explained above) for general data recovery of the national broadcast signal. On the lower portion of the receiver architecture, the measured combined local service insertion channel and national broadcast channel are fed onto an output 311 to a first input of a local equalizer 320. The estimate of the national broadcast signal left (7) 3 15 is fed to a multiplexer 322 which receives an estimate 310 of the combined local service insertion channel and national broadcast channel on a second input. A subtraction unit 3 24 then subtracts the estimate of the national broadcast symbol from the received signal multiplied by the product of the combined local service insertion and the national broadcast channel to form a local-34-201214986 service insertion that is fed to the local equalizer 320. Estimation of symbols. The internal structure of the local equalizer 320 is similar to the internal structure of the national broadcast signal equalizer. At the output of the local service insertion pilot splitter 326, the pilot signal is fed to a pilot demodulator 330 on an output 3 2 8 and then to a time slot unit 332, followed by a frequency interpolation unit 334. The frequency interpolation unit 344 forms an estimate of the channels through which the local service insertion symbols have passed. The estimate of the local service insertion data is fed to an divider 338 on an input 336 that receives the local service insertion symbol from another input 340 from the pilot splitter 326 and forms a local service insertion on an output 342. Estimation of data symbols. A demapper 344 and frequency deinterleaver 3M then form an estimate of the data representing the locally inserted data that it is fed to the descrambler 134. Thereafter, the data restoration of the locally inserted data is equivalent to the data restoration shown in relation to the data pipeline shown in FIG. It should be understood that another aspect of the present invention provides a first estimate of national broadcast material, which is then refined according to the judgment of the local service insertion symbol to form an estimate of further refinement of the national broadcast symbol, which can be used To further calculate an estimate of the refinement of the local service insertion symbol. Thus, a cyclic feedback configuration in the form of a turbo demodulation can be formed to provide further enhancements to the estimate of the received signal. Describing the operation, the operation of the receiver for restoring local data from the local service insertion symbol shown in Fig. 24 is illustrated by the flow chart shown in Fig. 25, which is described as follows: -35- 201214986 S2: Estimation of national broadcast symbols i(7) is formed by treating D(<z)[Ηα(ζ) + Η,(ζ)] as noise and cutting the recovered signal around the real and virtual planes to form a national broadcast. An estimate of the data was formed. S4: Using the primary subcarrier Ps to form an estimate of the combined channel transmitting the channel from the national broadcast base station and the local service insertion base station to calculate - a national broadcast representing the reproduction of the combined national broadcast and local service insertion channel convolution The estimate of the term of the signal f(z)[//„(Z) + //,(Z)]. S6: forming the volume and the local channel by subtracting the item generated from step S4 from the received signal. Estimation of the local service insertion symbol Z) (4) A (7) left (7) [/ / n (2) + 7 /, (7)]) S8: Use the local service insertion guide to determine the local service insertion channel that has passed from the base station to the receiver The estimate is (7). S 1 0 : The local service insertion data H is then estimated from the symbol generated by dividing the restored term by the estimate of the local channel, (z) various modifications of the above described invention can be made without departing from The spirit of the invention as defined in the appended claims is incorporated. For example, if the receiver is suitably adjusted, other modulation architectures than those described above may be used. Again, the modulation procedure may be repeated as described above. Several times to improve the received symbols Furthermore, the receiver can be used in a variety of systems that utilize OFDM modulation other than those defined by the DVB Handheld Standard. The content of this application claims the UK patent application GB 1 003 23 7.3 and GB </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> <RTIgt; References are made using the same numerical designations, and wherein: Figure 1 is a schematic representation of one of a plurality of base stations that form a single frequency network to broadcast, for example, part of a handheld DVB TV broadcast system. Figure 2 is a schematic block diagram of an example transmitter according to one of the prior art; Figure 3a is a schematic representation of a complex plane providing a graphical representation of the signal clustering points of the first modulation architecture of QPSK; Figure 3b A schematic representation of a complex plane, which provides an illustration of signal cluster points for a second modulation architecture of 16QAM, in accordance with the prior art; FIG. 4 is a diagram for use in one or more of the base stations shown in FIG. A schematic block diagram of a portion of the transmitter, in accordance with the invention supporting SISO or MISO; FIG. 5 is a schematic block diagram of an example modulator forming part of the transmitter shown in FIG. 4; Figure 2 shows the two adjacent base stations of cells A and B. The two cells A and B use the first modulation architecture of 16Q AM and the second modulation architecture of 64QAM. Figure 7 is a schematic diagram. Indicates that it shows the effect of cluster points received on three different locations X, Y, Z between the two base stations A and B of Figure 6 by the mobile device: Figure 8 is a stack of 64QAM Illustration of cluster points in the complex plane of the first modulation architecture of 16QAM on a two-modulation architecture; -37- 201214986 Figure 9a is a diagram of clusters of four cells served by four base stations in accordance with the present invention Figure 9b is a graphical representation of a graph of frequency versus time, providing a diagram of a time division multiplex frame structure; and Figure 9c is an illustration of a pattern of cell clusters in accordance with the present invention; Illustration of two adjacent base stations of two cells A and B, the two cells A and B are individually used 16QAM a modulation architecture and a second modulation architecture of 64Q AM; and using a mobile receiver configurable to restore local service insertion when signals from both the first modulation architecture and the second modulation architecture are present Data, in which the signal from cell B transmits a channel impulse in response to hn(t) and the signal from cell A transmits a channel impulse in response to hi (t); Figure 1 la is a schematic representation of a complex plane, which provides QPSK A schematic diagram of a signal cluster point of the first modulation architecture; and a schematic representation of the lb-based complex plane of FIG. 1 providing an illustration of a signal cluster point of the second modulation architecture of 16Q AM, wherein the reception is not miscellaneous And for a perfect channel estimate; Figure 12a is a schematic representation of a complex plane that provides an illustration of the signal cluster points of the first modulation architecture of QPSK, when received in the presence of a second modulation architecture, However, the signals from each cell transmit channels that respond through different channel impulses; and Figure 12b provides a corresponding representation of the same signal after performing equalization using a conventional equalizer with perfect channel estimates; Figure 13a is a complex number level The schematic diagram shows that it provides a graphical representation of the signal cluster point after subtracting SesJzHCHKzhHJz)); and Figure 13b shows the result of dividing the signal shown in Figure 13a by HKz), which assumes that the local service is inserted into the channel. HKz) is the perfect channel estimate that is known; -38- 201214986 Figure 14a is a diagram of a narrow-band carrier carrying the OFDM symbol of the national broadcast signal; Figure 14b is an OFDM symbol carrying the national broadcast signal and the local service insertion signal Diagram of a narrowband carrier; and Figure 14c is an illustration of a narrowband carrier carrying OFDM symbols of a local service insertion signal, but adapted to include local pilots in accordance with the present invention; Figure 15 is used in accordance with this A schematic block diagram of a transmitter in one or more base stations of the invention, which supports ΜΙΜΟ; Figure 16 is a signal noise for an OFDM transmitter-receiver chain of, for example, low density parity check (LDPC) coding Ratio of bit error rate to: 1/2, 3/5, 2/3, and 3/4 error correction coding rate; 16QAM first modulation architecture 64QAM second modulation architecture; and reception thereof Is considered to be located in cell A Within the coverage area and receiving an OFDM symbol having a signal power from base station A 99% and from base station B 1%, the signal from B arrives at the receiver at 4.375us after the signal from A, as in the example of FIG. Figure 17 is a graph of the bit error rate for the signal-to-noise ratio of an OFDM transmitter-receiver chain, for example, 1/2, 3/5, 2/3, and 3 /4 error correction coding rate; 16QAM first modulation architecture; 64Q AM second modulation architecture; and its receiver is considered to be located in the coverage area of cell A and received with 80% from base station A and from Base station B 2 0% of the signal power of the OFDM symbol, its signal from B arrives at the receiver 2.2μ5 after the signal from the base station A, as shown in the example diagram in Figure 6; Figure 18 is for (for example The LDPC-encoded OFDM transmitter receives a graph of the bit error rate of the signal-to-noise ratio of the -39-201214986 chain, with error correction coding rates of 1/2, 3/5, 2/3, and 3/4. The first modulation architecture of 16QAM; the second modulation architecture of 64Q AM: and its receiver is considered to be located in cell A Within the coverage area and receiving an OFDM symbol having a signal power from base station A 99% and from base station B 1%, with zero delay between signal arrival times from two cells, as shown in the example graph of FIG. Figure 19 is a graph of the bit error rate for the signal-to-noise ratio of an OFDM transmitter-receiver chain, for example, 1/2, 3/5, 2/3, and 3/4. Error correction coding rate; first modulation architecture of 16QAM; second modulation architecture of 04QAM; and its receiver is considered to be located in the coverage area of cell 并 and received with 60% from base station A and from base station B 40 OFDM symbol of % signal power with zero delay between signal arrival times from two cells, as shown in the example pattern in Figure 6; Figure 2 is for LDPC-encoded OFDM transmitter-received The plot of the bit error rate of the signal-to-noise ratio of the chain is: 1/2, 3/5, 2/3, and 3/4 error correction coding rate: 16QAM first modulation architecture; 64Q AM Two modulation architecture: and the receiver therein is considered to be located within the coverage area of cell A and received OFDM symbol from base station A 50% and signal strength from base station B 5 0%, with zero delay between signal arrival times from two cells, as shown in the example graph in Figure 6; Figure 21 For the graph of the bit error rate of the signal-to-noise ratio of the OFDM transmitter-receiver chain of, for example, LDPC, the error correction coding rate of 1/2, 3/5 and 2/3; the first of 16QAM Modulation architecture; the second modulation architecture of 64QAM; and the receiver in it is considered to be located in the coverage of cell B -40 - 201214986 and receives signal power with 10% from base station A and 90% from base station B The OFDM symbol, whose signal from A arrives at the receiver at a rate of 2·2 μ3 after the signal from the base station B, as shown in the example diagram of FIG. 6, and FIG. 22 is the receiver of the receiver according to an embodiment of the present invention. Figure 23 is a block diagram of a physical layer pipeline (PLP) appearing in the receiver of Figure 22; Figure 24 is a block diagram illustrating a receiver adapted in accordance with another exemplary embodiment of the present invention; And FIG. 25 is a flow chart illustrating the equalization of a single frequency signal. Example operation of the required program, including requirements from the first and second modulation architectures [Main component symbol description] 1 : Transmission antenna 2: Boundary 8: Modulator 3 0: Data pipeline 34: Scheduler 36: Transmit data processing pipeline 3 8: Input 40: Forward error correction encoder 42: Interleaver - 41 - 201214986 44: Modulator 50, 51, 52: Data slice processing unit 54: Frequency interleaver 56: Boot generator 58: framing unit 70: OFDM modulator 72: RF modulator 7 4: antenna 80: local service insertion data slice processor 8 2: first input 84: second input 90: data character former 92: Data character former 94: symbol selector 94.1: output 96: symbol selector 96.1: output 98: switching unit 100: control input 102: output channel 1 1 0: base station 1 1 2: base station 129, 130, 136 : PLP processing pipeline 134 : De-scheduler - 42 - 201214986 140 : Forward error correction decoder 142 : Deinterleaver 144 : QAM demodulator 146 : MISO / MIMO processor 150 : OFDM detector 1 5 8 : Frame Recovery Processor 174: Receiver Antenna 175: Radio Frequency Tuner 180: Local Boot Generator 182: Modulator 184: MISO Processing Unit 1 90: Block 192: Frequency Deinterleaver 194: Local Service Insert Data Block 200: Input 202: Output 290: Fast Fourier Transform FFT Block 292: National Broadcast Signal Equalizer 2 9 4 : Extended area 296 : Guide splitter 298 : Output 300 : Splitter unit 3 02 : Second output 3 04 : Time plug-in unit - 43 - 201214986 3 08 : Frequency interpolation unit 310 : Input 31 1 : Output 312 : National broadcast signal S (z) 3 1 4 : Demapper 315: Estimation of national broadcast signal 316 : Frequency deinterleaver 320 : Local equalizer 3 2 2 : Multiplexer 324 : Subtraction unit 326 : Local Service Insertion Guide Splitter 328: Output 3 3 0 : Guide Demodulator 33 2 : Time Interpolation Unit 334: Frequency Interpolation Unit 336: Input 3 3 8 : Splitter 3 40: Input 342: Output 344: Go Mapper 346: Frequency Deinterleaver - 44-