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1. 发明申请

WO1993007717A1 METHOD AND APPARATUS FOR SECURE TRANSMISSION OF VIDEO SIGNALS 审中-公开
标题翻译：用于安全传输视频信号的方法和设备
公开(公告)号：WO1993007717A1
公开(公告)日：1993-04-15
申请号：PCT/GB1992001785
申请日：1992-09-29
申请人： BRITISH BROADCASTING CORPORATION , THOMSON CONSUMER ELECTRONICS S.A. , ROBINSON, Adrian, Paul , CLARKE, Christopher, Keith, Perry , BOWER, Andrew, John , COCHON, Etienne , NACCACHE, David , POIVET, Michel , DORNER, Albert
发明人： BRITISH BROADCASTING CORPORATION , THOMSON CONSUMER ELECTRONICS S.A.
IPC分类号： H04N07/167
CPC分类号： H04N7/1696 , C07C67/29 , C08G63/21 , C08G63/676 , H04N7/17327
摘要： Video signals are sampled at 4Fsc locked onto sub-carrier phase and frequency. The active lines of each field are divided into 6 blocks of 47 lines and the active portions of those lines scrambled on a block by block basis by line shuffling. The shuffling algorithm is generated by a line shuffling permutator driven by a PRBS generator (controls 36, 38). Active line samples for one block are written in unscrambled form into a first memory block (32) and samples from the previous block are read out in scrambled form from a second memory block (34) for transmission. The complementary process takes place in the decoder.
摘要翻译：视频信号的采样频率等于4Fsc，频率锁定在副载波的相位和频率上。每个字段的有效行被分成6行，每行47行，并且这些行的有效部分是通过混排行逐块加扰的。混洗算法由由伪随机比特序列发生器控制的线交换置换器产生（命令36,38）。在第一存储块（32）中以非加扰形式记录块的有效行的样本，并且从第二存储块（34）从加扰存储器提取前一块的样本并从一个传输。补充过程发生在解码器中。

2. 发明申请

WO1992008315A1 METHOD AND APPARATUS FOR CLAMPING THE BLACK LEVEL OF A DIGITAL VIDEO SIGNAL 审中-公开
标题翻译：用于钳位数字视频信号的黑色电平的方法和装置
公开(公告)号：WO1992008315A1
公开(公告)日：1992-05-14
申请号：PCT/GB1991001870
申请日：1991-10-25
申请人： BRITISH BROADCASTING CORPORATION , CLARKE, Christopher, Keith, Perry
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04N05/16
CPC分类号： H04N5/185
摘要： A method for clamping the black level of a television signal comprises converting the input video signal to a digital input signal and, by means of a measuring circuit (10), measuring the signal level during a blanking period of the input video signal. The measured signal level is compared with a digital reference level to generate a digital error signal. A correction signal derived from the error signal at correction generator (14) is added to the samples forming the digital input signal with any residue of the truncated addition at each sample being retained for addition with the correction signal to the next sample.

3. 发明申请

WO1993007718A1 METHOD AND APPARATUS FOR SECURE TRANSMISSION OF VIDEO SIGNALS 审中-公开
标题翻译：用于安全传输视频信号的方法和装置
公开(公告)号：WO1993007718A1
公开(公告)日：1993-04-15
申请号：PCT/GB1992001786
申请日：1992-09-29
申请人： BRITISH BROADCASTING CORPORATION , ROBINSON, Adrian, Paul , CLARKE, Christopher, Keith, Perry , BOWER, Andrew, John
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04N07/167
CPC分类号： H04N7/1696 , C07C67/29 , C08G63/21 , C08G63/676 , H04N7/17327
摘要： Video signals are sampled at 4Fsc locked onto sub-carrier phase and frequency. The active picture lines of each field are divided into 6 blocks of 47 lines and the active line periods of those lines scrambled on a block by block basis by line order shuffling. The shuffling algorithm is generated by a line shuffling permutator driven by a PRBS generator (controls 36, 38). Active line period samples for one block are written in unscrambled form into a first memory block (32) and samples from the previous block are read out in scrambled form from a second memory block (34) for transmission. The complementary process takes place in the decoder.
摘要翻译：视频信号在4Fsc采样，锁定在子载波相位和频率上。每个场的活动图像行被划分成47行的6个块，并且这些行的有效行周期按行顺序改组逐个块地加扰。混洗算法由PRBS发生器驱动的线洗牌排列器产生（对照36,38）。一个块的有效行周期采样以未加扰的形式写入第一存储器块（32），并且来自前一块的采样以加扰形式从第二存储器块（34）读出以进行传输。互补过程发生在解码器中。

4. 发明申请

WO1988000783A1 IMPROVEMENTS RELATING TO TELEVISION 审中-公开
标题翻译：关于电视的改进
公开(公告)号：WO1988000783A1
公开(公告)日：1988-01-28
申请号：PCT/GB1987000499
申请日：1987-07-15
申请人： BRITISH BROADCASTING CORPORATION , CHILDS, Ian , CLARKE, Christopher, Keith, Perry
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04N07/087
CPC分类号： H04N5/145 , G06T7/262 , H04N7/0155 , H04N7/0157 , H04N7/125 , H04N9/646 , H04N11/006 , H04N11/02 , H04N11/167 , H04N19/43 , H04N19/51 , H04N19/523 , H04N19/527 , H04N19/547 , H04N19/59 , H04N19/80
摘要： A PAL television signal is modified in that the vertical blanking interval includes a plurality of data items each representing picture-dependent, e.g. movement, information from a related area of the picture being transmitted, there being typically several thousand such areas. The additional data may be used in a receiver to improve decoding by switching between picture-delay and line-delay decoding, or to assist in upconversion to a higher line and/or field standard for display by varying the type of interpolation used.
摘要翻译：修改PAL电视信号，因为垂直消隐间隔包括多个数据项，每个数据项表示图像相关，例如。移动，来自正在发送的图片的相关区域的信息，通常有几千个这样的区域。附加数据可以用在接收机中以通过在图像延迟和线延迟解码之间切换来改进解码，或者通过改变所使用的插值类型来辅助上变频到更高的线和/或场标准以进行显示。

5. 发明申请

WO1994018795A1 TELEVISION SYSTEMS 审中-公开
标题翻译：电视系统
公开(公告)号：WO1994018795A1
公开(公告)日：1994-08-18
申请号：PCT/GB1994000252
申请日：1994-02-09
申请人： BRITISH BROADCASTING CORPORATION , CLARKE, Christopher, Keith, Perry
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04N07/00
CPC分类号： H04N21/2383 , H04N7/015 , H04N7/24 , H04N19/00 , H04N21/4382
摘要： An enhanced digital television signal is transmitted within a conventional television waveform by modulating the digital signals onto active picture area lines of the conventional waveform. This may be achieved by first modulating a set of orthogonal waveforms with the digital signals and then transmitting the modulating orthogonal waveforms on the active picture area lines. At a decoder the reverse process takes place.
摘要翻译：通过将数字信号调制到常规波形的有源图像区域线上，在传统的电视波形内传输增强的数字电视信号。这可以通过首先用数字信号调制一组正交波形，然后在活动图像区域线上发送调制正交波形来实现。在解码器处，进行相反的处理。

6. 发明申请

WO1997016942A1 METHOD AND APPARATUS FOR REDUCTION OF UNWANTED FEEDBACK 审中-公开
标题翻译：减少反馈信息的方法和装置
公开(公告)号：WO1997016942A1
公开(公告)日：1997-05-09
申请号：PCT/GB1996002643
申请日：1996-10-30
申请人： BRITISH BROADCASTING CORPORATION , STOTT, Jonathan, Highton , WELLS, Nicholas, Dominic
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04R03/02
CPC分类号： H04R3/02 , H03H21/0012 , H04B7/15564
摘要： The feedback caused between the output (39) and the input (30) of an amplification path (54, 42, 56, 60, 62, 64) is reduced by providing a delay (60) in the amplification path, passing through the amplification path a signal having an auto-correlation function which is substantially a delta function, correlating (72) the said signal before being delayed in the delay with the signal after being delayed in the delay to produce a plurality of correlation coefficients, modifying the signal in the amplification path to provide a modified signal, the modification being provided by a transversal filter (76) controlled by the said plurality of correlation coefficients, and combining (42) the modified signal with the signal in the amplification path so as to reduce the effect of the feedback. The signal having an auto-correlation function which is substantially a delta function may be an added noise signal (70) or may be constituted by the signal being processed itself. The system can be used to reduce "howl-around" in audio situations or feedback in simultaneous coherent re-broadcast transceivers.
摘要翻译：通过在放大路径中提供延迟（60），通过放大路径（54,42,56,60,62,64）的输出（39）和放大路径（54,42,56,60,62,64）的输入（30）路径具有基本上是Δ函数的自相关函数的信号，将在延迟中延迟之前的所述信号与延迟后延迟的信号相关（72）以产生多个相关系数，修改所述放大路径用于提供修改的信号，所述修改由所述多个相关系数控制的横向滤波器（76）提供，并且将所述修改的信号与所述放大路径中的所述信号组合（42）以便减小所述效果的反馈。具有基本上为Δ函数的自相关函数的信号可以是附加噪声信号（70），或者可以由被自身进行处理的信号构成。该系统可用于减少音频情况中的“嚎叫”或同时相干重新广播收发器中的反馈。

7. 发明申请

WO1996001535A1 HIERARCHICAL OFDM 审中-公开
标题翻译：分层OFDM
公开(公告)号：WO1996001535A1
公开(公告)日：1996-01-18
申请号：PCT/GB1995001586
申请日：1995-07-05
申请人： BRITISH BROADCASTING CORPORATION , MADDOCKS, Mark, Charles, Dobell , STOTT, Jonathan, Highton
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04L05/06
CPC分类号： H04L27/2605 , H04L23/02 , H04L27/2604
摘要： An orthogonal frequency division multiplexed (OFDM) signal is coded by dividing each OFDM symbol into a plurality of mini-symbols. Carriers (A, B, C, D) in each mini-symbol are formed from different portions of a plurality of signal sets (J, K, L, M). The most important data is coded on a signal set which provides a substantially constant contribution to the corresponding carriers in each mini-symbol and is thus conveyed most ruggedly. Less important data is coded on signal sets which vary between corresponding carriers from mini-symbol to mini-symbol in dependence on predetermined functions and is thus conveyed less ruggedly. The contributions from these signal sets sum substantially to zero across an OFDM symbol. Alternatively the signal sets coded with the most important data are assigned every rth carrier forming an OFDM symbol and signal sets coded with less important data are assigned to intermediate carriers wherein each intermediate carrier is coded with data derived from a plurality of signal sets. In each of these systems the most important data serves as a phase and amplitude reference for the signal sets carrying less important data.
摘要翻译：通过将每个OFDM符号划分为多个迷你符号来对正交频分复用（OFDM）信号进行编码。每个迷你符号中的载体（A，B，C，D）由多个信号组（J，K，L，M）的不同部分形成。最重要的数据被编码在信号组上，该信号组对每个迷你符号中的对应载波提供基本上恒定的贡献，并且因此最坚固地传送。不太重要的数据被编码在根据预定功能从迷你符号到迷你符号的相应载波之间变化的信号集上，因此不那么坚固地传送。来自这些信号集合的贡献在OFDM符号上大致上归零。或者，用最重要的数据编码的信号组被分配给形成OFDM符号的每第r个载波，并且用不太重要的数据编码的信号集被分配给中间载波，其中每个中间载波用从多个信号集得到的数据进行编码。在这些系统的每个系统中，最重要的数据用作携带较不重要数据的信号集的相位和幅度参考。

8. 发明申请

WO1995024780A1 DIGITAL BROADCAST SYSTEMS FOR LOCAL TRANSMISSIONS 审中-公开
标题翻译：用于本地传输的数字广播系统
公开(公告)号：WO1995024780A1
公开(公告)日：1995-09-14
申请号：PCT/GB1995000536
申请日：1995-03-10
申请人： BRITISH BROADCASTING CORPORATION , MADDOCKS, Mark, Charles, Dobell
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04H01/00
CPC分类号： H04H20/18 , H04H20/42 , H04H20/61 , H04H20/67 , H04H2201/20 , H04L27/2602 , H04L27/2614 , H04L27/2621
摘要： A digital signal is transmitted in a coded orthogonal frequency division multiplex (COFDM) signal as a series of time frames. Each frame comprises a plurality of time domain symbols derived from the orthogonal frequency domain multiplex of at least one digital signal. The frames are separated by null symbols which are used by receivers for synchronisation. A group of symbols in each frame are assigned to each digital signal to be transmitted by a transmitter. Symbols which are to be used for transmission of other signals by adjacent transmitters are left blank but their power levels are raised above the threshold for null symbol detection by a K receiver. A compatible receiver is thereby able to distinguish between null symbols and symbols which are empty of data.
摘要翻译：数字信号以编码的正交频分复用（COFDM）信号作为一系列时间帧发送。每个帧包括从至少一个数字信号的正交频域复用导出的多个时域符号。这些帧由接收器用于同步的空符号分开。每个帧中的一组符号被分配给要由发射机发送的每个数字信号。用于由相邻发射机传输其他信号的符号留空，但其功率电平升高到高于阈值，由K接收机进行空符号检测。因此，兼容的接收机能够区分零符号和空数据的符号。

9. 发明申请

WO1993009616A1 CODING METHOD FOR BROADCAST TRANSMISSIONS 审中-公开
标题翻译：广播传输的编码方法
公开(公告)号：WO1993009616A1
公开(公告)日：1993-05-13
申请号：PCT/GB1992001997
申请日：1992-11-02
申请人： BRITISH BROADCASTING CORPORATION , CHAMBERS, John, Philip
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H04H01/00
CPC分类号： H04H20/30 , H04H20/67 , H04H60/54 , H04H2201/20 , H04L27/2627 , H04L27/2649
摘要： A broadcast transmission using a frequency-division multiplex technique, such as the so-called DAB or DSB proposed radio system, uses a large number of carriers generated by coding digital information using a fast Fourier transform (12). Additional data is carried by relatively varying the amplitudes of the carriers in a modification circuit (26) by a slight amount in accordance with the additional data. The additional data may comprise transmitter identification. The additional data can be recovered by decision logic (46) in a receiver.

10. 发明申请

WO1992015151A1 SQUARE-ROOT ANTI-SYMMETRIC FILTERS 审中-公开
标题翻译：平方根反对称滤波器
公开(公告)号：WO1992015151A1
公开(公告)日：1992-09-03
申请号：PCT/GB1992000259
申请日：1992-02-13
申请人： BRITISH BROADCASTING CORPORATION , DREWERY, John, Oliver
发明人： BRITISH BROADCASTING CORPORATION
IPC分类号： H03H17/02
CPC分类号： H03H17/02
摘要： A filter is produced having a real and an imaginary part, such that for positive frequencies the frequency characteristic F of the filter is F = A + jS. The real part A is a skew-symmetric filter and S is a real symmetric filter symmetric about the cut point. S is related to A by S = X[A(1-A)]. Once A has been chosen the filter can be derived. A method of forming the filter involves deriving symmetrical and antisymmetrical windows from the filters frequency characteristic A and S and combining the windows to form an asymmetric window.

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