九、發明說明·· 發明所屬之技術領域 本發明是關於確保無線通 利用在傳輸階段於…丄 ★尤其是關於一種 ^1於一通訊信號上涵蓋浮水印的方A，逵到_ 保無線通訊安全性之方法和裝置。 W方式’達到確 先前技術 由於其本身性質的關係’容易因攻擊而使安 到影響’而這些系統不斷地發展成長，更擴 k二缺點。舉例來說’即便是點對點(ad hoc)網路亦 P固別用戶直接互相通訊而不使用中繼網路節點，依然會因 攻擊而使安全性、隱私權、個人身份等等受到影響。 為了減少無線通訊系統固有的缺失，目前在無線通訊系統中 已經使用像是有線等價隱私權（WEP)、Wi_Fi保護存取 (WPA)、延伸認證協定（ΕΑΡ)、IEEE 802.lli、以及以行動通 訊全球系統(GSM)為基礎之加密技術。然而，儘管這些技術 提供了一些程度的保護’無線通訊系統依然容易受到攻擊。 舉例來說，如果一個無線使用者使用WEP安全技術作為其 確保無線通訊安全性之裝置’而該使用者接收來自一個擁有 正確WEP安全錄匙之未知網路節點的通訊，由於該通訊包 含正確的1WEP錄匙，因此會告知該使用者此通訊係來自於 一個受到信任的來源，然而，因為該使用者對於該發送節點 不熟悉，且因為WBP錄匙报可能被其他無線通訊系統入侵 1330486 和複製，使用者可能便不太願意「信任」該通訊，而且，即 ' 便一個惡劣使用者或駭客並未擁有正確的WEP安全鑰匙， . 由於這些鑰匙的認證一般都於通訊層的較高層執行，該惡劣 - 使用者或是駭客便可存取該通訊層，並且在認證之前執行像 . 是拒絕服務的攻擊。 目前有一種查證和確保媒體内容安全性的技術稱為浮水 印。浮水印，亦稱為「内容浮水印」，乃是一種增加隱藏查 鲁核及/或安全資料於不同形式的媒體内容中，數位浮水印則 將此概念擴展至數位媒體。然而，内容浮水印技術是設計來 保護相對靜態或是不會改變形式的内容，因此，在確保動態 ' 内容安全性方面，像是在動態無線環境中傳輸無線通訊，傳 統的内容浮水印便不適合作為一種保護技術。 因此，便需要一種提供增強浮水印機制之方法和裝置，其能 確保在動態無線環境中之無線通訊信號發送的安全性。 發明内容 本發明是關於一種確保無線通訊安全性之方法和裝置。一浮 水印訊息係編碼為浮水印訊息符號。一涵蓋訊息係編碼為涵 蓋訊息符號。該浮水印訊息符號接著疊覆在該涵蓋訊息符號 上，以便在實體層產生一浮水印内嵌涵蓋訊息。該浮水印訊 息實際上具有比該涵蓋訊息更低的振幅，因此，該浮水印訊 息在該涵蓋訊息符號之信號分佈點（constellation point)周圍 7 1330486 便造成微小的擾動。該浮水印訊息可在複數個涵蓋訊息符號 上擴張或展開，且可以一安全鑰匙加密。該浮水印訊息可藉 由傳輸額外的資訊而改善無線通訊效能，或是僅用以增強安 全性的確保。浮水印的功能亦可選擇性地開啟或關閉。 實施方式 當此後提到「傳輸器」及「接收器」，其包含但不限制於， 一無線傳輸/接收單元(WTRU)、一使用者設備(UE)、一行動 站台、一固定或行動用戶單元、一呼叫器、一節點B、一基 地台、一站台控制器、一存取點、或是其他任何可用於一無 線環境中的裝置。 本發明之特徵可整合至一積體電路(1C)中，或是配置在一個 包含許多互連元件的電路中。 第1圖所示為一個根據本發明的無線通訊系統100方塊圖， 其包含一個用以編碼浮水印的傳輸器110，以及一個用以解 碼浮水印的接收器120。該傳輸器110包含一個浮水印編碼 器112及一個傳輸處理器116。該浮水印編碼器112接收一 個浮水印訊息111以及一個涵蓋訊息113，且輸出一個浮水 印内嵌涵蓋訊息115,該涵蓋訊息113係為欲由該傳輸器 110，透過空氣介面之頻道118所傳輸至該接收器120之資 料，而該浮水印訊息111則為欲連同該涵蓋訊息113 —起傳 輸的資料，因此該浮水印内嵌涵蓋訊息115可視為一種多工IX. INSTRUCTION DESCRIPTION OF THE INVENTION TECHNICAL FIELD The present invention relates to ensuring that wireless communication is used in the transmission phase. In particular, it relates to a party A that covers a watermark on a communication signal. Safety methods and devices. The W method has achieved the prior art. Because of its own nature, it is easy to be affected by the attack, and these systems continue to grow and develop. For example, even an ad hoc network does not allow users to communicate directly with each other without using a relay network node, which still affects security, privacy, personal identity, etc. due to attacks. In order to reduce the inherent lack of wireless communication systems, wire-equivalent privacy (WEP), Wi_Fi Protected Access (WPA), Extended Authentication Protocol (ΕΑΡ), IEEE 802.11i, and Mobile Communications Global System (GSM)-based encryption technology. However, while these technologies provide some level of protection, wireless communication systems are still vulnerable. For example, if a wireless user uses WEP security technology as its means of securing wireless communications' and the user receives communications from an unknown network node with the correct WEP security key, since the communication contains the correct 1WEP key, so the user is informed that the communication is from a trusted source, however, because the user is not familiar with the sending node, and because the WBP keying report may be invaded by other wireless communication systems 1330486 and copied Users may be less willing to "trust" the communication, and, that is, a bad user or hacker does not have the correct WEP security key. Because the authentication of these keys is generally performed at a higher level of the communication layer. The bad - the user or the hacker can access the communication layer and perform an attack like a denial of service before authentication. There is currently a technology for verifying and ensuring the security of media content called floating. Watermarking, also known as "content watermarking", is an increase in hidden racore and/or security material in different forms of media content. Digital watermarking extends this concept to digital media. However, content watermarking technology is designed to protect content that is relatively static or does not change its form. Therefore, traditional content watermarking is not suitable for ensuring dynamic 'content security, such as transmitting wireless communication in a dynamic wireless environment. As a protection technology. Therefore, there is a need for a method and apparatus for providing an enhanced watermarking mechanism that ensures the security of wireless communication signal transmission in a dynamic wireless environment. SUMMARY OF THE INVENTION The present invention is directed to a method and apparatus for securing wireless communications. A floating watermark message is encoded as a watermark message symbol. A cover message is coded to cover the message symbol. The watermark message symbol is then overlaid on the covered message symbol to generate a watermark embedded coverage message at the physical layer. The watermarking information actually has a lower amplitude than the covered message, and therefore, the watermarking message causes a slight perturbation around the signal distribution point of the covered message symbol. The watermark message can be expanded or expanded over a plurality of covered message symbols and can be encrypted with a secure key. The watermark message can improve the performance of the wireless communication by transmitting additional information, or can only be used to enhance the security. The function of the watermark can also be selectively turned on or off. Embodiments are referred to hereinafter as "transmitters" and "receivers", including but not limited to, a WTRU, a user equipment (UE), a mobile station, a fixed or mobile user. A unit, a pager, a Node B, a base station, a station controller, an access point, or any other device that can be used in a wireless environment. Features of the invention may be integrated into an integrated circuit (1C) or in a circuit comprising a plurality of interconnected components. 1 is a block diagram of a wireless communication system 100 in accordance with the present invention, including a transmitter 110 for encoding a watermark, and a receiver 120 for decoding a watermark. The transmitter 110 includes a watermark encoder 112 and a transport processor 116. The watermark encoder 112 receives a watermark message 111 and a cover message 113, and outputs a watermark embedded cover message 115, which is to be transmitted by the transmitter 110 through the channel 118 of the air interface. The data to the receiver 120, and the watermark message 111 is the data to be transmitted along with the coverage message 113, so the watermark embedded coverage message 115 can be regarded as a multiplex
8 通訊形式。 =水印訊息111可Μ料安錢或是改善馳效能，1 水印訊息111可選擇性地由該浮水i f 處理並透過該頻道118二 '』’在此期間該傳輸信號117可能”受攻擊。 根據本發明，該浮水印訊息 訊自m 在實體層中内嵌於該涵蓋 “3,此κ體層處理過程可加 二且不需要改變習知的空氣介面標準即可引入該：據機 選二:發明·水印機能可與傳統的空氣介 : 、擇性地開啟和關閉’藉由開啟或關閉在？ 的機能，以選擇性地產生安全鍊結。 …、内部 =圖所示為根據本發明之浮水印 水印編碼5| 112包含一侗、τ ^ 6 1窃UZ万塊圖。該洋 射單元二二器個符號映 映射及內ns 4 以及—個浮水印符號 器該涵蓋訊息113係由該涵蓋訊息編碼 梦咏沪/丁編豸’接者’編碼過之涵蓋訊息203便藉由該符 旒映射早元204捕至一涵蓋訊息符!#υ2〇5。該浮水印訊息 U1係由該浮水印編碼器206進行編碼（選擇性地，以一秘密 鑰114編馮）’經過編碼的浮水印訊息207接著便由該浮ς 印符號映射及内嵌單元208，映射至該信號分佈點^中之 1330486 一，並疊覆在該涵蓋訊息符號205上，以產生一個浮水印内 嵌涵蓋訊息符號115。 該浮水印符號映射及内嵌單元可在内牵制該涵蓋訊息符號 之前，以一固定角度旋轉該編碼浮水印訊息符號之信號分 佈。 當開啟浮水印機能時，便會啟動該浮水印編碼器206和該浮 水印符號映射及内嵌單元208，以便編碼該浮水印訊息 111(選擇性地使用該秘密鑰114)，且疊覆在該涵蓋訊息符號 205上，以便產生該浮水印内嵌涵蓋訊息符號115。如果關 閉該浮水印機能，便會中斷該浮水印編碼器206及該浮水印 符號映射及内嵌單元208，且該浮水印編碼器112會輸出該 涵蓋訊息符號205。因此，本發明首先藉由維持該浮水印信 號之低信號等級（因此會以一個額外的低等級雜訊信號來源 出現），且再者可開啟或關閉該浮水印，而可維持與習知系 統的相容性。 根據本發明，該浮水印訊息111係直接疊覆在該涵蓋訊息 113上，如第3圖所示。該涵蓋訊息113係為一個二元信號， 其係編碼成複數個符號，每該符號由該浮水印編碼器根據一 個調變機制映射至其中一個信號分佈點，而該調變機制可為 二相移位鍵控（BPSK)、QPSK、四相振幅調變（QAM)等等。 舉例來說，如果該涵蓋訊息113係使用QPSK調變，則該涵 10 1330486 蓋訊息113中，每兩個位元便會映射至四個信號分佈點 S1-S4的其中之一，如同第4A圖所示。 ” ，浮水印訊息111亦為—個二減號，其係由該浮水印編碼 态根據調便機制編碼成符號，該調便機制可為 QPSK、QAM、正交頻分多工(〇FDM)、正交頻分多重存取 (OFDMA)等等。該浮水印訊4⑴之符號係疊覆至該涵蓋 訊息113之符號上，如同第3及祁圖所示。舉例來說在 第4B圖中，該涵蓋訊息113及該浮水印訊息^丨係 QPSK調變’且將料水印訊息⑴之純疊覆在該涵蓋訊 息113之上之後，該信號分佈點（由四個星號表示）便合落在 ，四圖中的每該四個信號分佈點S1_S4周圍。值得二意的 是’該涵蓋訊息113及該浮水印訊息lu可由任 钢 變機制調變，這對熟習此技藝之人士來說是顯而易見^。·· ί上=實ΠΓ浮水㈣⑽涵蓋訊息m之符號率執 ;實==巧別!要。一般來說’該浮水印訊息⑴具 有貫質上比該涵盍訊息113的振幅還要低的振幅，因此，該 夺水印訊息符號便會以微小的擾動出現在該涵蓋訊轳 之信號分佈點S1-S4的周圍，如第4B圖所示。〜" 由於擾動很微小的關係，個別的浮水印訊4 iu之符 在蓋訊息符號上展開’以確保在該接收器齡且有 一個a適的信號對雜訊比(SNR)。該展開可#由下列^ 丄·3：>υ4δ0 之义在數個,函蓋訊息符號上複製該浮水印訊息、或是在調變 月J使用—編碼器，例如一個迴旋編碼器（⑶ 個:水印訊息位元映射至數個位元，其係展開數 號符％1^符號°或者’該浮水印訊息符號可在數個涵蓋信 涵°蓋：號：：’其係藉由以擾亂碼或是一擴展碼，在複數個 號妒i。上擴展’其係類似於碼分多重存取(CDMA)信 動作，以去展開該執仃-個符號去複製或是去展開的 饮開夺水印訊息符號。 圖，圖签所Γ圖為Φ個根據本發明之淨水印内嵌涵蓋訊息說明8 Form of communication. = Watermark message 111 can be used to save money or improve performance. 1 Watermark message 111 can be selectively processed by the floating water if and transmitted through the channel 118'' during which the transmitted signal 117 may be "attacked." According to the present invention, the watermark message is embedded in the physical layer from the coverage "3, and the κ layer processing process can be added and the conventional air interface standard does not need to be changed to introduce the standard: Invention · Watermarking function can be combined with traditional air: Selectively open and close 'by turning it on or off? The ability to selectively create a secure link. ..., internal = figure shows the watermark watermarking code 5|112 according to the present invention comprising a 侗, τ ^ 6 1 thief UZ million block diagram. The symbolic mapping of the two elements of the oceanic-emitting unit and the inner ns 4 and the water-splitting watermarker are covered by the message 203, which is encoded by the cover-message coded Nightmare/Ding Editing 'Connector'. With this symbol map, the early element 204 captures a covered message! #υ2〇5. The watermark message U1 is encoded by the watermark encoder 206 (optionally, encoded by the secret key 114). The encoded watermark message 207 is then mapped and embedded by the floating symbol. And mapped to the 1330486 one of the signal distribution points and overlaid on the coverage message symbol 205 to generate a watermark embedded coverage message symbol 115. The watermark symbol mapping and embedding unit may rotate the signal distribution of the encoded watermark message symbol at a fixed angle prior to pinning the cover message symbol. When the watermarking function is enabled, the watermark encoder 206 and the watermark symbol mapping and embedding unit 208 are activated to encode the watermarking message 111 (optionally using the secret key 114) and overlaid on The message symbol 205 is overlaid to produce the watermark embedded message symbol 115. If the watermark function is turned off, the watermark encoder 206 and the watermark symbol mapping and embedding unit 208 are interrupted, and the watermark encoder 112 outputs the covered message symbol 205. Therefore, the present invention can be maintained and conventionally maintained by maintaining a low signal level of the watermark signal (and thus appearing as an additional source of low level noise signals) and again turning the watermark on or off. Compatibility. According to the present invention, the watermark message 111 is superimposed directly on the cover message 113 as shown in FIG. The coverage message 113 is a binary signal encoded into a plurality of symbols, each of the symbols being mapped by the watermark encoder to one of the signal distribution points according to a modulation mechanism, and the modulation mechanism may be two phases. Shift Keying (BPSK), QPSK, Four Phase Amplitude Modulation (QAM), etc. For example, if the coverage message 113 is modulated using QPSK, then each of the two bits is mapped to one of the four signal distribution points S1-S4, as in the 4A. The figure shows. The watermarking message 111 is also a two-subtraction number, which is encoded into a symbol according to the tuning mechanism by the watermarking encoded state, and the tuning mechanism can be QPSK, QAM, or orthogonal frequency division multiplexing (〇FDM). Orthogonal Frequency Division Multiple Access (OFDMA), etc. The symbol of the watermark 4(1) is overlaid onto the symbol of the cover message 113, as shown in Figures 3 and 3. For example, in Figure 4B After the coverage message 113 and the watermarking message are QPSK modulated and the material watermark message (1) is superimposed on the coverage message 113, the signal distribution point (represented by four asterisks) is combined. In each of the four signal distribution points S1_S4 in the four figures, it is worth noting that the coverage message 113 and the watermark message lu can be modulated by any steel transformation mechanism, which is for those skilled in the art. Obviously ^.·· 上=实ΠΓ浮水(四)(10) Covers the symbol rate of the message m; real == 巧别!要. In general, the watermark message (1) has a quality that is better than the amplitude of the 盍 message 113 To have a low amplitude, therefore, the watermarking message symbol will appear with a small disturbance Covers the signal distribution points S1-S4 around the signal, as shown in Figure 4B. ~" Due to the very small relationship between the disturbances, the individual watermarks 4 iu are expanded on the cover message symbol to ensure that Receiver age and have an appropriate signal-to-noise ratio (SNR). The expansion can be copied by the following ^ 丄 · 3: > υ 4δ0 on several, the cover message symbol to copy the watermark message, or Is used in the modulation month J - encoder, such as a cyclotron encoder ((3): watermark message bit mapping to a number of bits, which is the expansion number symbol %1 ^ symbol ° or 'the watermark message symbol can be In several coverages, the cover: number:: 'is extended by a number of 妒i. by means of a scrambling code or a spreading code, which is similar to a code division multiple access (CDMA) signal action. To unfold the stub--a symbol to copy or unfold the drink to open the watermark message symbol. The figure is marked as Φ. According to the present invention, the net watermark embedded cover message description
信號分佈ϋ㈣印訊息符號F加至該QPSK 一個合成輸出向量（亦即的—個涵蓋訊息符號以，以便產生 說，在第i象限中艾I:個浮水印内嵌符號)卜般來 l-Si+W 成内嵌符號向量无’係表示為： 其中Μ系為該第i’方程式（1) 信號分佈中的浮水印^ /符號，而W係為在該QPSK 用之調變_⑽卩·ν；錢向4。由襲蓋訊息符號所使 符號而有解同。冑㈣分_)’可依該浮水印訊息 假設該浮水印訊息符號 號向量妒係為一個隨機向量，其具有 零均數及〜的變異，則兮 賣'予水印内戒訊息之平均SNR便為： ^ φ ;方程式(2) ........收集信號沿之期望值（或平均值），下標/ :S) 12 1330486 ''為、、且值的索引，σ〖及則分別代表該浮水印訊息的 變異及追加白高斯雜訊（AWGN, additive white Gaussian noise)，而|£咚+ %}|2則為該浮水印訊息符號及該涵蓋訊息符號 之總和的平均功率。 如方私式(2)所示，該涵蓋訊息符號之平均功率（或振幅）並未 改變’這是因為由該浮水印訊息符號所引起之加顫動訊號Signal distribution 四 (4) The printed message symbol F is added to the QPSK. A composite output vector (ie, the cover message symbol is used to generate, say, in the i-th quadrant, I: a watermark embedded symbol). The Si+W inline symbol vector without 'system is expressed as: where Μ is the watermark ^ / symbol in the signal distribution of the i'th equation (1), and W is the modulation _ (10) used in the QPSK · ν; money to 4. It is resolved by the symbol made by the cover message symbol.胄(4)分_)' can assume that the watermark message symbol number vector is a random vector, which has zero mean and ~ variation, and then sells the average SNR of the watermark or the message. For: ^ φ ; Equation (2) ........ Collect the expected value (or average value) along the signal, subscript / :S) 12 1330486 '', and the index of the value, σ 〖 and Representing the variation of the watermark message and adding white Gaussian noise (AWGN) respectively, and |£咚+%}|2 is the average power of the sum of the watermark message symbol and the covered message symbol. As shown in (2), the average power (or amplitude) of the covered message symbol does not change. This is because the jitter signal caused by the watermark message symbol.
(dithering)之緣故，但是該涵蓋訊息之SNR會因為該浮水印 訊息所引起之信號分佈點模糊（smearing)而有所降低。 或者該涵蓋讯息符號及該浮水印訊息符號可在傳輸遽波之(dithering), but the SNR of the covered message is reduced due to the smearing of the signal distribution caused by the watermark message. Or the covered message symbol and the watermark message symbol can be transmitted in the chopping
後組合，且該涵蓋訊息符號之符號時序相位可因應該浮水印 訊息符號而改變。舉例來說，一個錯位半個符號之信號將以 一净水印訊息符號之邊緣對齊該涵蓋訊息符號之中央。第 7A-7C圖所示即為涵蓋訊息符號及一個具有時序偏差之浮 水印内嵌涵蓋訊息符號的信號分佈點，其係根據本發明。如 第7A圖所示’假設在％之一涵蓋訊息符號為&，而如第 圖所不，在τ】之一涵蓋訊息符號為S2，藉由將該 位半個符號時間’該浮水印訊息符號 ^覆: ㈣轉換㈣的中間，如第7B_示。1 Τΐ/2&覆在 照第i圖’在此將描述該浮水印内嵌 理。該接收器12〇包含一接收處理器122 ;:二處 器124、以及一浮水印解 必減息解妈 1 126 ° 一傳輸的浮水印内嵌信 13 號丨21係透過空氣介面 並且由該接收處理器122二7由該接收器⑽所接收， 所產生之-信㈣係輪入理。由該接收處理器⑵ 浮水印解碼哭126球、至該涵盍訊息解碼器124以及該 號123產生^函蓋訊息解碼器124由該處理過之信 符號⑵125⑽絲算該涵蓋訊息 浮水印解碼器〗26，二便蓋！息符號125輸入至該 ^幫助偵測洋水印符號。該浮水印偵 」:::==，一-息符號: =:=:==涵蓋信號之信號 A 逆涵盡訊息解碼器124於兮、7 7息上所做的符號決定’可使復原該浮水印訊Φ lu = π^Γ^ϊΓΤηΓ-4 111 112以一秘讀114加後，該復原 裔 印解碼器126以一秘密鑰128解密。該洋水 圖赫為鮮水㈣嵌信號之符號錢 方便，在第6圖巾是假設該 :為了訓 QPSK，而該浮水印位元之調變機 = 是之調變機t是 ::大小為8。符號Sij表示、函蓋訊息以 為…水印位元為。:::二訊= 息符號為S1且一浮水印位元為卜為了說 1330486 中，該涵蓋訊息符號S1之偵測區域係表為D(S1)。一般 來說，該浮水印位元之内嵌會降低該涵蓋訊息符號之偵測效 能，此測量係如下所述，舉例來說，該信號分佈點之實部和 虛部分別用X和y表示，而該S1之涵蓋訊息的符號錯誤 率（亦即符號錯誤之機率P)，可依據如下方程式獲得： |5l}=l-f [/{x^dxdy ； 方程式(3) 其中，sf為當該傳輸涵蓋訊息符號為SI時，在該接收器端 的估算涵蓋訊息符號，而f(x,y)表示該接收信號123 (在第 1圖中）之X和y的接合機率密度函數，乃6SV則表示Si 之一偵測區域。方程式（3)的左側係為估算涵蓋訊息符號不 等於傳輸涵蓋訊息符號，且因此成為一個錯誤事件的機率， 方程式（3)右側的積分則為估算涵蓋訊息符號等於傳輸符號 之總機率，以1減去該積分便是該符號錯誤的機率。因該 浮水印訊息符號所引起之加顫動訊號，而使該涵蓋訊息符號 偵測的效能降級測量，可以使用一執行損失表示，其係藉由 具有浮水印之符號錯誤率對SNR，與不具有浮水印之符號 錯誤率對SNR，這兩者的曲線差異作為指示。 習知技術中，像是傳輸或是訓練序列、頻道編碼/解碼、交 錯/去交錯、速率符合、展開/去展開、加密/解密等等，可由 傳輸器110及接收器120在浮水印訊息111上執行，以提供 免除通訊頻道和不同攻擊形式之影響，並保護其避免遭到竊 聽。 15 1330486 本發明之機制亦可用於OFDM系統。在子載波上的調變符 號可由一浮水印訊息111以類似的方法擾動，其係藉由疊覆 浮水印符號於該調變符號（亦即涵蓋訊息符號）上，該浮水印 訊息符號可在數個涵蓋訊息符號上展開，以便藉由複製或是 頻道編碼而在該接收器端獲得一個適當的SNR。或者，該 浮水印訊息111可在數個涵蓋信號符號上擴展，其係藉由以 擾亂碼或是一擴展碼擴展，或是藉由在複數個涵蓋信號符號 上擴展之一擴展碼擴展。 本發明之浮水印機制可用於改善接收器效能、改善通訊系 統、或是增強安全性。改善接收器效能可藉由將額外的資訊 編碼成為該浮水印訊息111達成，使得該額外的訊息令一接 收器在一個較低的SNR上運作以達到相同的效能，或是使 用額外的資訊以達到相同SNR下的更好效能。舉例來說， 該浮水印訊息111可為額外的同位元，其係來自一頻道編碼 器、幫助在該接收器中之等化器的頻道狀態資訊、或是時序 資訊，以便該接收器中能有同調接收（coherent reception)。 除此之外，該通訊系統之效能改善，可藉由透過該浮水印頻 道傳輸像是旁側資訊或控制資訊等額外資訊達成。舉例來 說，在多媒體廣播下，該浮水印訊息可用以作為旁側資訊， 像是一個壓制該廣播服務之一公開通知，以作為該涵蓋訊 息。 改善安全性之達成，可藉由引入已知的資料作為該浮水印訊Post-combination, and the symbol timing phase of the coverage message symbol may change due to the watermark message symbol. For example, a misaligned half symbol signal will be aligned with the edge of the covered message symbol with the edge of a clear watermark message symbol. Figures 7A-7C show signal distribution points covering message symbols and a floating watermark embedded message symbol with timing offset, in accordance with the present invention. As shown in Fig. 7A, 'assuming that one of the % covers the message symbol is & and as the figure does not, one of the τ's covers the message symbol S2, and by the bit half symbol time 'the watermark The message symbol ^ is overwritten: (4) The middle of the conversion (4), as shown in the 7B_. 1 Τΐ/2& is covered in Fig. i. The watermark embedding will be described herein. The receiver 12A includes a receiving processor 122; a two-way device 124, and a watermarking solution for the interest-reduction of the mother 1 126 ° a watermark embedded letter 13 丨 21 through the air interface and by the The receiving processor 122 is received by the receiver (10), and the generated (four) wheel is processed. The receiver processor (2) performs a watermark decoding cry 126 ball, to the culvert message decoder 124, and the number 123 generates a message decoder 124 to calculate the covered message watermark decoder from the processed message symbol (2) 125 (10) 〗 26, two will cover! The symbol 125 is input to the ^ to help detect the ocean watermark symbol. The watermark detection":::==, one-interest symbol: =:=:== The signal A of the cover signal is inverted. The symbol decision made by the decoder 124 on the 兮, 7 7 can be restored. The watermarking signal Φ lu = π ^ Γ ^ ϊΓΤ Γ 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 111 The foreign water figure is convenient for fresh water (four) embedded signal symbol, in the sixth figure is assumed to be: in order to train QPSK, and the watermark bit modulation machine = is the modulation machine t is:: size Is 8. The symbol Sij represents, the cover message is ... the watermark bit is. ::: 2 = The symbol is S1 and a watermark bit is used. In order to say 1330486, the detection area of the covered message symbol S1 is D(S1). In general, the embedding of the watermarking bit reduces the detection performance of the covered message symbol. The measurement is as follows. For example, the real and imaginary parts of the signal distribution point are represented by X and y, respectively. And the symbol error rate of the covered message of S1 (that is, the probability of symbol error P) can be obtained according to the following equation: |5l}=lf [/{x^dxdy; Equation (3) where sf is when the transmission When the message symbol is SI, the estimation at the receiver side covers the message symbol, and f(x, y) represents the probability density function of the X and y of the received signal 123 (in FIG. 1), which is 6SV. One of the Si detection areas. The left side of equation (3) is the probability that the estimated coverage message symbol is not equal to the transmission coverage message symbol and therefore becomes an error event. The integral on the right side of equation (3) is the total probability that the estimated coverage message symbol is equal to the transmission symbol. Subtracting the score is the probability that the symbol is wrong. Due to the fluttering signal caused by the watermark message symbol, the performance degradation measurement of the covered message symbol detection may use an execution loss representation, which is achieved by using a watermarked symbol error rate versus SNR, and without The watermark's symbol error rate versus SNR, the difference in the curve between the two is used as an indication. In the prior art, such as transmission or training sequence, channel encoding/decoding, interleaving/deinterleaving, rate matching, expansion/de-expansion, encryption/decryption, etc., the watermarking message 111 can be used by the transmitter 110 and the receiver 120. Execute to provide an exemption from communication channels and different forms of attack and protect them from eavesdropping. 15 1330486 The mechanism of the present invention can also be applied to OFDM systems. The modulation symbol on the subcarrier can be perturbed by a watermark message 111 in a similar manner by overlaying the watermark symbol on the modulation symbol (ie, covering the message symbol), the watermark message symbol can be A number of coverage message symbols are expanded to obtain an appropriate SNR at the receiver by copying or channel coding. Alternatively, the watermark message 111 can be spread over a number of covered signal symbols by spreading with a scrambling code or a spreading code, or by spreading a spreading code over a plurality of covering signal symbols. The watermarking mechanism of the present invention can be used to improve receiver performance, improve communication systems, or enhance security. Improving receiver performance can be achieved by encoding additional information into the watermark message 111 such that the additional message enables a receiver to operate at a lower SNR to achieve the same performance, or to use additional information to Achieve better performance at the same SNR. For example, the watermark message 111 can be an additional peer, which is derived from a channel encoder, channel state information that assists the equalizer in the receiver, or timing information so that the receiver can There is coherent reception. In addition, the performance improvement of the communication system can be achieved by transmitting additional information such as side information or control information through the watermark channel. For example, under multimedia broadcast, the watermark message can be used as side information, such as a public notice to suppress the broadcast service as the coverage information. Improved safety can be achieved by introducing known data as the watermark
A 16 1330486 息達成，該編碼僅由該傳輸器和接收器所知，以便更改具有 及不具有該浮水印頻道之接收器所知曉的SNR，以降低遺忘 該浮水印資料之接收器的效能。舉例來說，該浮水印可使用 加顫動訊息，以於該傳輸波形上產生一個明顯瞭解的額外雜 訊，僅有知道該浮水印資訊的接收器可消掉由該浮水印所產 生的明顯雜訊。 儘管本發明之特徵和元件皆於實施例中以特定組合方式所 描述，但實施例中每一特徵或元件能獨自使用，而不需與較 佳實施方式之其他特徵或元件組合，或是與/不與本發明之 其他特徵和元件做不同之組合。儘管本發明已經透過較佳實 施例描述，其他不脫附本發明申請專利範圍之變型，對熟習 此技藝之人士來說還是顯而易見的。A 16 1330486, the code is known only by the transmitter and receiver to change the SNR known to the receiver with and without the watermark channel to reduce the performance of the receiver forgetting the watermark data. For example, the watermark can use a fluttering message to generate an additional unknown noise on the transmitted waveform, and only the receiver that knows the watermark information can eliminate the obvious miscellaneous generated by the watermark. News. Although the features and elements of the present invention are described in a particular combination of the embodiments, each feature or element of the embodiments can be used alone, without being combined with other features or elements of the preferred embodiment, or with / No combination of other features and elements of the invention. While the invention has been described in terms of a preferred embodiment, it will be apparent to those skilled in the art.
17 1330486 圖式簡單說明 藉由下文中一較佳實施例之描述、所給予的範例，並參照對 應的圖式，本發明可獲得更詳細地瞭解，其中： 第1圖所示為一個用以編碼和解碼浮水印之無線通訊系統 方塊圖，其係根據本發明所配置； 第2圖所示為一個根據本發明之浮水印編碼器的詳細方塊 圖， 第3圖所示為一個在一涵蓋訊息上疊覆一浮水印訊息之說 明圖，其係根據本發明所實施； 第4A圖所示為一個在執行增加浮水印之前，進行四相移位 鍵控（QPSK)信號分佈的說明圖； 第4B圖所示為一個在執行增加浮水印之後，進行QPSK信 號分佈之說明圖，其係根據本發明所實施； 第5圖所示為一個根據本發明之浮水印内嵌涵蓋信號的說 明圖， 第6圖所示為一個根據本發明之一給定涵蓋信號之偵測區 域的說明圖；以及 第7A-7C圖係以時序偏差來表示涵蓋訊息符號及一浮水印 内嵌涵蓋訊息符號之信號分佈點，其係根據本發明所實施。 元件符號說明 100 無線通訊系統 117傳輸信號 115 浮水印内概涵蓋訊息123信號 205 涵蓋訊息符號 121浮水印内嵌信號 1817 1330486 BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more fully understood by the following description of the preferred embodiments, the examples given, and the accompanying drawings, wherein: FIG. A block diagram of a wireless communication system for encoding and decoding a watermark, which is configured in accordance with the present invention; FIG. 2 is a detailed block diagram of a watermark encoder in accordance with the present invention, and FIG. 3 is a An explanatory diagram of superimposing a watermark message on the message, which is implemented according to the present invention; FIG. 4A is an explanatory diagram of performing a four phase shift keying (QPSK) signal distribution before performing the addition of the watermark; Figure 4B is an explanatory diagram showing the distribution of the QPSK signal after performing the addition of the watermark, which is implemented according to the present invention; and Figure 5 is an explanatory diagram of the embedded signal of the watermark embedded in accordance with the present invention. Figure 6 is an explanatory diagram showing a detection area of a covered signal according to one of the present inventions; and 7A-7C is a timing deviation indicating a covered information symbol and a watermark embedded The signal distribution point of the cover message symbol is implemented in accordance with the present invention. Component Symbol Description 100 Wireless Communication System 117 Transmission Signal 115 The watermark covers the message 123 signal 205 Covers the message symbol 121 Watermark embedded signal 18