公开(公告)号：US09473335B2

公开(公告)日：2016-10-18

申请号：US13456850

申请日：2012-05-11

申请人： Carl Scarpa ,  Edward Schell ,  Christopher Strolle

发明人： Carl Scarpa ,  Edward Schell ,  Christopher Strolle

IPC分类号： H04L27/32 ,  H04L27/04 ,  H04L27/26 ,  H04L27/34

CPC分类号： H04L27/04 ,  H04L27/01 ,  H04L27/2601 ,  H04L27/265 ,  H04L27/3461 ,  H04L27/3488 ,  H04L69/324

摘要： Systems and methods are presented for transmitting additional data over preexisting differential COFDM signals by changing the amplitude of the legacy data symbols. In exemplary embodiments of the present invention, additional data capacity can be achieved for a COFDM signal which is completely backwards compatible with existing legacy satellite broadcast communications systems. In exemplary embodiments of the present invention, additional information can be overlaid on a legacy COFDM signal by applying an amplitude offset to the legacy symbols. In exemplary embodiments of the present invention, special receiver processing can be implemented to extract this additional information, which can include performing channel equalization across frequency bins to isolate the amplitude modulated overlay signal. For example, at each FFT symbol time, average power across neighboring active data bins can be used to determine the localized power at the corresponding FFT bins, and a channel inversion can then, for example, be performed on the data bins to restore, as best as possible, the original transmitted symbol amplitude.

摘要翻译： 提出了系统和方法，用于通过改变传统数据符号的幅度来传输先前存在的差分COFDM信号的附加数据。 在本发明的示例性实施例中，可以实现与现有传统卫星广播通信系统完全向后兼容的COFDM信号的附加数据容量。 在本发明的示例性实施例中，通过对遗留符号应用振幅偏移，附加信息可以覆盖在传统COFDM信号上。 在本发明的示例性实施例中，可以实现特殊的接收机处理以提取该附加信息，该附加信息可以包括在频率仓之间执行信道均衡以隔离调幅叠加信号。 例如，在每个FFT符号时间，可以使用相邻的活动数据箱之间的平均功率来确定相应FFT仓上的局部功率，然后可以例如对数据仓进行信道反转以恢复，如 最好尽可能的，原来传输的符号幅度。

公开(公告)号：US08306145B2

公开(公告)日：2012-11-06

申请号：US12416027

申请日：2009-03-31

申请人： Carl Scarpa ,  Edward Schell ,  Christopher Strolle

发明人： Carl Scarpa ,  Edward Schell ,  Christopher Strolle

IPC分类号： H04L27/10

CPC分类号： H04L27/2627 ,  H04L5/0007 ,  H04L5/0028 ,  H04L27/0008 ,  H04L27/0012 ,  H04L27/183 ,  H04L27/2053 ,  H04L27/2071 ,  H04L27/3488 ,  H04L2025/03401 ,  H04L2025/03414

摘要： Systems and methods are presented for transmitting additional data over preexisting differential COFDM signals by modulating existing data carriers with a phase and an amplitude offset. In exemplary embodiments of the present invention, additional data capacity can be achieved for an COFDM signal which is completely backwards compatible with existing satellite broadcast communications systems. In exemplary embodiments of the present invention additional information can be overlayed on an existing signal as a combination of amplitude and phase offset from the original QPSK symbols, applied for each information bit of the overlay data. With two additional levels of modulation, a receiver can demodulate the information from each of the previous stages and combine the information into a suitable format for soft decoding. The first stage of demodulation will be recovery of overlay data from the amplitude modulated D8PSK. Because other amplitude variations due to multi-path are also expected, the data gathered from the FFT in the receiver must be equalized to the channel conditions. After channel equalization has been performed, soft overlay data can then be derived from the distance off the unit circle. In order to recover the phase modulated overlay data, the equalized symbols must first be differentially demodulated and corrected for any common phase error offset. After common phase removal, overlay phase information can be obtained.

摘要翻译： 提出了系统和方法，用于通过调制具有相位和幅度偏移的现有数据载波来传输先前存在的差分COFDM信号的附加数据。 在本发明的示例性实施例中，可以实现与现有卫星广播通信系统完全向后兼容的COFDM信号的附加数据容量。 在本发明的示例性实施例中，作为叠加数据的每个信息比特的原始QPSK符号的幅度和相位偏移的组合，附加信息可以叠加在现有信号上。 通过两个附加的调制级别，接收机可以解调来自每个先前阶段的信息，并将该信息组合成用于软解码的适当格式。 解调的第一阶段将是从幅度调制的D8PSK恢复覆盖数据。 由于也预期由于多路径引起的其他幅度变化，所以从接收机中从FFT收集的数据必须与信道条件相等。 在执行信道均衡之后，可以从距离单位圆的距离导出软覆盖数据。 为了恢复相位调制覆盖数据，必须首先对均衡的符号进行差分解调并校正任何公共相位误差偏移。 共相除去后，可以获得覆盖相位信息。

公开(公告)号：US08139689B2

公开(公告)日：2012-03-20

申请号：US12079782

申请日：2008-03-28

申请人： Carl Scarpa ,  Edward Schell

发明人： Carl Scarpa ,  Edward Schell

IPC分类号： H03D3/22

CPC分类号： H04L27/2271 ,  H04L27/183

摘要： Systems and methods for removing phase shifts due to hierarchical modulation to improve synchronization and performance in legacy and hierarchical decoders are presented. To compensate for the effects of hierarchical modulation, such methods include receiving an I,Q symbol that has been further modulated by an overlay phase shift, detecting the direction of the overlay phase shift, de-rotating the symbol by a defined angle corresponding to the overlay phase shift and said direction; and passing the symbol to legacy synchronization and forward error correction decoding stages after said de-rotating. An exemplary receiver can be provided to implement the disclosed methods.

摘要翻译： 提出了用于消除由分级调制引起的相移以改善传统和分层解码器中的同步和性能的系统和方法。 为了补偿分级调制的影响，这种方法包括接收已经被覆盖相移进一步调制的I，Q符号，检测叠加相移的方向，将符号去旋转与 覆盖相移和所述方向; 并且在所述去旋转之后将符号传递到传统同步和前向纠错解码阶段。 可以提供示例性接收机来实现所公开的方法。

公开(公告)号：US20090168809A1

公开(公告)日：2009-07-02

申请号：US12183980

申请日：2008-07-31

申请人： Carl Scarpa ,  Edward Schell

发明人： Carl Scarpa ,  Edward Schell

IPC分类号： H04J3/06

CPC分类号： H04L27/183 ,  H04J7/00 ,  H04L7/043 ,  H04L7/06 ,  H04L27/3488

摘要： Methods and apparatus are presented for the joint synchronization of legacy signals with overlay modulation signals in a communications system utilizing a hierarchical modulation scheme. In exemplary embodiments of the present invention, a synchronization signal can be sent in each of the legacy and overlay bit streams, each using a different approach to frame synchronization, and the two synchronization signals can be used in a complementary manner to synchronize both bit streams. In exemplary embodiments of the present invention a legacy physical frame and an overlay physical frame can be aligned in time. In exemplary embodiments of the present invention a key synchronization signal in a legacy bit stream can be time distributed throughout a legacy transmission frame and can be utilized to assist in both the synchronization of such legacy bit stream and of an overlay bit stream. Additionally, in exemplary embodiments of the present invention, a key synchronization signal in an overlay bit stream can be sent in one fixed physical frame of an overlay transmission frame, and can be utilized to assist in the synchronization of such overlay bit stream as well as legacy data, in a manner that complements the use of the synchronization signal provided in the legacy bit stream.

摘要翻译： 提出了在利用分级调制方案的通信系统中传统信号与覆盖调制信号的联合同步的方法和装置。 在本发明的示例性实施例中，可以在传统和覆盖比特流中的每一个中发送同步信号，每个使用与帧同步不同的方法，并且可以以互补方式使用两个同步信号来同步两个比特流 。 在本发明的示例性实施例中，传统物理帧和覆盖物理帧可以在时间上对准。 在本发明的示例性实施例中，传统比特流中的密钥同步信号可以在传统传输帧中被时分布置，并且可以用于协助这种传统比特流和覆盖比特流的同步。 另外，在本发明的示例性实施例中，重叠比特流中的密钥同步信号可以在覆盖传输帧的一个固定物理帧中发送，并且可以用于协助这种覆盖比特流的同步以及 遗留数据，以补充传统比特流中提供的同步信号的使用的方式。

公开(公告)号：US20060145918A1

公开(公告)日：2006-07-06

申请号：US11346643

申请日：2006-02-03

申请人： John Henderson ,  Carl Scarpa

发明人： John Henderson ,  Carl Scarpa

IPC分类号： H01Q3/00

CPC分类号： H01Q1/007 ,  H01Q1/24 ,  H01Q3/2611 ,  H01Q7/005

摘要： Antennas with steerable antenna patterns and techniques for using such antennas are described. In accordance with the invention, antenna patterns with one or more NULLs are used. Through the use of digital control signals the antenna pattern is steered so that a source of signal interference, e.g., a multipath signal, will be located in a NULL. In this manner the received signal's S/N ratio can be maximized thereby facilitating demodulation. The techniques of the invention can be applied to television, computer devices, mobile devices and a wide range of other systems. Digital commands to control an antenna may include multiple information fields, e.g., a direction field, a channel field, a gain field and a polarity field. Antennas incapable of supporting the specified fields disregard information in fields which are not supported. Information in each supported field is decoded and used to adjust the corresponding antenna characteristic.

公开(公告)号：US08332718B2

公开(公告)日：2012-12-11

申请号：US12079467

申请日：2008-03-26

申请人： Carl Scarpa ,  Edward Schell

发明人： Carl Scarpa ,  Edward Schell

IPC分类号： G06F11/00

CPC分类号： H03M13/6505 ,  H03M13/05 ,  H03M13/1105 ,  H03M13/3746

摘要： Systems and methods are presented to improve the performance of a constant bit rate iterative decoder by providing elastic buffering, while utilizing a relatively simple decoder architecture capable of maintaining a fixed number of iterations of a lower value. An LDPC decoder can be designed, for example, to support less than the maximum possible number of iterations, and can, for example, be mated to elastic input and output buffers. If a given code block, or succession of code blocks, requires the maximum number of iterations for decoding, the decoder can, for example, run at such maximum number of iterations and the elastic input buffer can, for example, hold code blocks waiting to be processed so as to maintain a constant input rate. Alternatively, if one or more code blocks requires less than the nominal number of iterations, the output buffer can store those code blocks so as to preserve a constant output rate. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, and is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.

摘要翻译： 提出了系统和方法，以通过提供弹性缓冲来提高恒定比特率迭代解码器的性能，同时利用能够维持较低值的固定次数迭代的相对简单的解码器架构。 例如，LDPC解码器可以被设计为支持小于最大可能的迭代次数，并且可以例如与弹性输入和输出缓冲器配合。 如果给定代码块或连续的代码块需要用于解码的最大迭代次数，则解码器可以例如以这样的最大迭代次数运行，并且弹性输入缓冲器可以例如保持等待 进行处理以保持恒定的输入速率。 或者，如果一个或多个代码块需要小于标称的迭代次数，则输出缓冲器可以存储那些代码块，以便保持恒定的输出速率。 要强调的是，提供本摘要以符合要求抽象的规则，并提交了一项谅解，即不会将其用于解释或限制权利要求书的范围或含义。

公开(公告)号：US20090279418A1

公开(公告)日：2009-11-12

申请号：US12416027

申请日：2009-03-31

申请人： Carl Scarpa ,  Edward Schell ,  Christopher Strolle

发明人： Carl Scarpa ,  Edward Schell ,  Christopher Strolle

IPC分类号： H04J13/00 ,  H04J11/00

CPC分类号： H04L27/2627 ,  H04L5/0007 ,  H04L5/0028 ,  H04L27/0008 ,  H04L27/0012 ,  H04L27/183 ,  H04L27/2053 ,  H04L27/2071 ,  H04L27/3488 ,  H04L2025/03401 ,  H04L2025/03414

摘要： Systems and methods are presented for transmitting additional data over preexisting differential COFDM signals by modulating existing data carriers with a phase and an amplitude offset. In exemplary embodiments of the present invention, additional data capacity can be achieved for an COFDM signal which is completely backwards compatible with existing satellite broadcast communications systems. In exemplary embodiments of the present invention additional information can be overlayed on an existing signal as a combination of amplitude and phase offset from the original QPSK symbols, applied for each information bit of the overlay data. With two additional levels of modulation, a receiver can demodulate the information from each of the previous stages and combine the information into a suitable format for soft decoding. The first stage of demodulation will be recovery of overlay data from the amplitude modulated D8PSK. Because other amplitude variations due to multi-path are also expected, the data gathered from the FFT in the receiver must be equalized to the channel conditions. After channel equalization has been performed, soft overlay data can then be derived from the distance off the unit circle. In order to recover the phase modulated overlay data, the equalized symbols must first be differentially demodulated and corrected for any common phase error offset. After common phase removal, overlay phase information can be obtained.

摘要翻译： 提出了系统和方法，用于通过调制具有相位和幅度偏移的现有数据载波来传输先前存在的差分COFDM信号的附加数据。 在本发明的示例性实施例中，可以实现与现有卫星广播通信系统完全向后兼容的COFDM信号的附加数据容量。 在本发明的示例性实施例中，作为叠加数据的每个信息比特的原始QPSK符号的幅度和相位偏移的组合，附加信息可以叠加在现有信号上。 通过两个附加的调制级别，接收机可以解调来自每个先前阶段的信息，并将该信息组合成用于软解码的适当格式。 解调的第一阶段将是从幅度调制的D8PSK恢复覆盖数据。 由于也预期由于多路径引起的其他幅度变化，所以从接收机中从FFT收集的数据必须与信道条件相等。 在执行信道均衡之后，可以从距离单位圆的距离导出软覆盖数据。 为了恢复相位调制覆盖数据，必须首先对均衡的符号进行差分解调并校正任何公共相位误差偏移。 共相除去后，可以获得覆盖相位信息。

公开(公告)号：US07209433B2

公开(公告)日：2007-04-24

申请号：US10041082

申请日：2002-01-07

申请人： Carl Scarpa

发明人： Carl Scarpa

IPC分类号： H04J11/00 ,  H04J3/12

CPC分类号： H04L25/0236 ,  H04L25/025 ,  H04L27/2647

摘要： Methods and apparatus for performing channel estimate updates in frequency division multiplexed, e.g., (OFDM), systems are described. After generation of initial channel estimates from received pilots, channel estimates corresponding to individual tones are updated using any one of a plurality of update techniques including, e.g., a constant modulus based method and a reduced constellation decision directed update method. The channel estimate update technique to be used with for an individual tone is selected based on a comparison of a signal noise measurement to one or more thresholds. The channel estimate update technique applied to different tones of the OFDM signal at the same time may vary. Over time, as the level of noise is reduced, the channel estimate update technique will switch from an interpolated pilot method, to a constant modulus algorithm based method, to a reduced constellation decision directed method, to a full constellation decision directed update method.

摘要翻译： 描述了用于在频分复用（例如，（OFDM））系统中执行信道估计更新的方法和装置。 在从接收到的导频生成初始信道估计之后，使用多种更新技术中的任何一种来更新对应于各个音调的信道估计，所述更新技术包括例如基于恒模的方法和减少的星座决策定向更新方法。 基于信号噪声测量与一个或多个阈值的比较来选择要用于单个音调的信道估计更新技术。 同时应用于OFDM信号的不同音调的信道估计更新技术可以变化。 随着时间的推移，随着噪声水平的降低，信道估计更新技术将从内插导频方法转换为基于恒模算法的方法，以减少星座决策方法，转换为全星座决策定向更新方法。

公开(公告)号：US07006040B2

公开(公告)日：2006-02-28

申请号：US10020703

申请日：2001-11-30

申请人： John G. N. Henderson ,  Carl Scarpa

发明人： John G. N. Henderson ,  Carl Scarpa

IPC分类号： H01Q3/24

CPC分类号： H01Q1/007 ,  H01Q1/24 ,  H01Q3/2611 ,  H01Q7/005

摘要： Antennas with steerable antenna patterns and techniques for using such antennas are described. In accordance with the invention, antenna patterns with one or more NULLs are used. Through the use of digital control signals the antenna pattern is steered so that a source of signal interference, e.g., a multipath signal, will be located in a NULL. In this manner the received signal's S/N ratio can be maximized thereby facilitating demodulation. The techniques of the invention can be applied to television, computer devices, mobile devices and a wide range of other systems. Digital commands to control an antenna may include multiple information fields, e.g., a direction field, a channel field, a gain field and a polarity field. Antennas incapable of supporting the specified fields disregard information in fields which are not supported. Information in each supported field is decoded and used to adjust the corresponding antenna characteristic.

公开(公告)号：US06668027B1

公开(公告)日：2003-12-23

申请号：US09490612

申请日：2000-01-25

申请人： Carl Scarpa

发明人： Carl Scarpa

IPC分类号： H04L2708

CPC分类号： H04B1/0003 ,  H04B1/406

摘要： Methods and apparatus for performing gain control in a manner that is designed to maximize the use of the dynamic range of signal processing circuitry, e.g., an A/D converter, while minimizing signal clipping are described. In one embodiment a power reference level used for automatic gain control purposes is periodically adjusted. An exemplary state machine of the present invention has an analysis state which collects signal statistics, e.g., signal clipping and threshold statistics, for a period of time corresponding to a fixed number of samples. During the analysis state, the number of samples that equal or exceed either the minimum or maximum valid values (e.g., clip points), supported by the signal processing circuitry, are accumulated. Statistics are also accumulated on the number of data samples that exceed thresholds, e.g., +/−tail thresholds, corresponding to points near the outer portion of the range supported by the signal processing circuitry. At the end of each analysis period, a decision is made to decrease the AGC power reference level if points were clipped, or increase the AGC power reference level if no points exceeded the tail thresholds. If neither the condition to raise nor the condition to lower the AGC power reference level is satisfied, no change is made to the power reference level. The state machine of the present invention can be used as an AGC circuit to directly control the adjustment of the gain of a signal.

摘要翻译： 描述了以最小化信号处理电路（例如，A / D转换器）的动态范围的最大化使信号限幅最小化的方式进行增益控制的方法和装置。 在一个实施例中，周期性地调整用于自动增益控制目的的功率参考电平。 本发明的示例性状态机具有在对应于固定数量的采样的时间段内收集信号统计信号（例如信号限幅和阈值统计）的分析状态。 在分析状态期间，累积由信号处理电路支持的等于或超过最小或最大有效值（例如，剪辑点）的采样数。 对于超过由信号处理电路所支持的范围的外部部分附近的点的超过阈值（例如+/-尾部阈值）的数据样本的数量也进行统计。 在每个分析周期结束时，如果点被削减，则决定降低AGC功率参考电平，或者如果没有点超过尾部阈值，则增加AGC功率参考电平。 如果既不满足升高条件也不满足降低AGC功率基准电平的条件，则不改变功率基准电平。 本发明的状态机可以用作AGC电路，以直接控制信号增益的调整。