公开(公告)号：US06347071B1

公开(公告)日：2002-02-12

申请号：US09170057

申请日：1998-10-13

申请人： Robert Louis Cupo ,  Mohsen Sarraf ,  Mojtaba Shariat ,  Mohammad Hossein Zarrabizadeh

发明人： Robert Louis Cupo ,  Mohsen Sarraf ,  Mojtaba Shariat ,  Mohammad Hossein Zarrabizadeh

IPC分类号： H04J1100

CPC分类号： H04L5/023

摘要： An orthogonal frequency division multiplexing (OFDM) technique which is time division multiplexed to reduce the overall effect on individual services from conditions such as selective fading. In accordance with the principles of the present invention, all available subcarriers in a channel are assigned to fewer than all of the requesting services, e.g., to just one particular service for a period of time. The period of time is preferably independent of the length of a conventional data frame. Thereafter, a second service is assigned access to the use of all available subcarriers for a period of time corresponding to its required bandwidth, and so on until all requesting services are allotted a portion of time for access to all available subcarriers. Any one service may utilize any number of the available subcarriers in a particular superframe containing one cycle of transmissions for all services.

摘要翻译： 正交频分复用（OFDM）技术，其被时分多路复用以从诸如选择性衰落的条件减少对各个服务的总体影响。 根据本发明的原理，信道中的所有可用子载波被分配给少于全部请求服务，例如分配给仅一个特定服务一段时间。 该时间段优选地与常规数据帧的长度无关。 此后，第二服务被分配对所有可用子载波的使用对应于其所需带宽的一段时间的访问，等等，直到所有请求服务被分配用于访问所有可用子载波的一部分时间。 任何一个服务可以在包含用于所有服务的一个传输周期的特定超帧中利用任何数量的可用子载波。

公开(公告)号：US09787413B2

公开(公告)日：2017-10-10

申请号：US14563882

申请日：2014-12-08

申请人： Walid Khairy Mohamed Ahmed ,  Mohsen Sarraf ,  Xiaopeng Huang

发明人： Walid Khairy Mohamed Ahmed ,  Mohsen Sarraf ,  Xiaopeng Huang

IPC分类号： H04B11/00

CPC分类号： H04B11/00

摘要： Circuits, systems and methods that utilize two transducers, of which at least one is a piezoelectric transducer, adapted and coupled to receive and/or generate signals in the forms of sound waves, mechanical vibrations, and/or electromagnetic energy. In one version, two transducers each receive and/or generate separate vibrational energy signals that bear information. Two or more transducers coupled to a switching circuit may send or receive piezo-electrical circuit output signals that include a carrier wave having different frequencies that are within separate frequency ranges. Two or more transducers may generate output signals that are simultaneously processed by or multiplexed by a switching circuit.

公开(公告)号：US07881342B2

公开(公告)日：2011-02-01

申请号：US12239524

申请日：2008-09-26

申请人： Maryam Mirmobini ,  Mohsen Sarraf ,  Chris Vaios

发明人： Maryam Mirmobini ,  Mohsen Sarraf ,  Chris Vaios

IPC分类号： H04L29/04

CPC分类号： H04L69/04 ,  H04L65/607 ,  H04N21/235 ,  H04N21/23614 ,  H04N21/4348 ,  H04N21/435 ,  H04N21/812

摘要： A system and method for providing ancillary data over compressed multimedia packets. Ancillary data may be added to encoded or compressed packets without increasing the bandwidth required to transmit the packets over a transmission medium. After transmission, the ancillary data can be recovered and the packets restored to their original form without any loss of data or damage to original content. The ancillary data can be presented to a user on-demand, or in response to an event. The content of the ancillary data can also be correlated to the type of event that initiated the delivery or to the content of the encoded or compressed packets.

摘要翻译： 一种用于通过压缩的多媒体分组提供辅助数据的系统和方法。 辅助数据可以被添加到编码或压缩的分组，而不增加在传输介质上传送分组所需的带宽。 传输后，可以恢复辅助数据，并将数据包恢复到原始形式，而不会丢失数据或损坏原始内容。 辅助数据可以按需呈现给用户，或响应于事件。 辅助数据的内容还可以与发起传送的事件的类型或编码或压缩的数据包的内容相关联。

公开(公告)号：US07542736B2

公开(公告)日：2009-06-02

申请号：US11189210

申请日：2005-07-26

申请人： Mohsen Sarraf

发明人： Mohsen Sarraf

IPC分类号： H04B1/04

CPC分类号： H04B1/707 ,  H04B2201/70706

摘要： Techniques to reduce signal amplitude peak-to-average ratio (PAR) in a wireless communications system are described. The apparatus may include a signal conditioning module to receive a baseband signal. The signal conditioning module may split the baseband signal along multiple paths, delay one or more of the paths, and combine the multiple paths to form a conditioned signal having lower signal amplitude PAR than the baseband signal. Other embodiments are described and claimed.

摘要翻译： 描述了在无线通信系统中降低信号幅度峰均比（PAR）的技术。 该装置可以包括用于接收基带信号的信号调节模块。 信号调理模块可以沿着多个路径分割基带信号，延迟一个或多个路径，并且组合多个路径以形成具有比基带信号更低的信号幅度PAR的调节信号。 描述和要求保护其他实施例。

公开(公告)号：US20080304677A1

公开(公告)日：2008-12-11

申请号：US11761891

申请日：2007-06-12

申请人： Amir ABOLFATHI ,  Mohsen Sarraf

发明人： Amir ABOLFATHI ,  Mohsen Sarraf

IPC分类号： G10K11/178 ,  G10K11/00

CPC分类号： G10K11/178 ,  G10K2210/12 ,  G10K2210/3215

摘要： A system and method for noise cancellation is disclosed herein generally having at least one microphone, a processor, and a speaker array. The processor may contain an adaptive filtering feature, to separate desirable sound from undesirable sound. The undesirable sound may be suppressed by the processor by creating a canceling waveform and transmitting the canceling waveform to the user's head via a speaker array. The desirable sound may be enhanced by increasing the amplitude of the waveform and transmitting the amplified waveform to the user's head via a speaker array. The sound transmitted to the user's head by the system may be localized using an image tracking subsystem and speaker array. The image tracking system may track the actual visible image or alternatively a heat (e.g. infrared) image of the user's head.

摘要翻译： 本文公开了一种用于噪声消除的系统和方法，其通常具有至少一个麦克风，处理器和扬声器阵列。 处理器可以包含自适应滤波特征，以将期望的声音与不期望的声音分离。 可能由处理器通过产生消除波形并且经由扬声器阵列将消除波形发送到用户的头部来抑制不期望的声音。 可以通过增加波形的幅度并通过扬声器阵列将放大的波形发送到用户的头部来增强期望的声音。 通过系统传输到用户头部的声音可以使用图像跟踪子系统和扬声器阵列来定位。 图像跟踪系统可以跟踪实际的可见图像，或者跟踪用户头部的热（例如红外）图像。

公开(公告)号：US07072592B2

公开(公告)日：2006-07-04

申请号：US09681720

申请日：2001-05-25

申请人： Mohsen Sarraf

发明人： Mohsen Sarraf

IPC分类号： H04J14/02 ,  H04B10/06

CPC分类号： H04J14/02 ,  H04B10/506

摘要： An apparatus provides an optical wavelength division multiplexed signal having 2M optical channels such that each of M information-bearing signals are differentially encoded onto 2 of the 2M optical channels. In particular, the apparatus comprises M inverters, 2M electrical-to-optical converters and a multiplexer. Each electrical-to-optical converter provides an optical signal at a different one of 2M wavelengths. The apparatus receives the M information-bearing signals and (a) creates M optical signals, each at a different wavelength, by converting each of the M information bearing signals into the optical domain via M of the 2M electrical-to-optical converters, and (b) creates M inverted optical signals, each at a different wavelength, by first inverting each of the M information bearing signals (via the M inverters) before conversion into the optical domain via the remaining M electrical-to-optical converters. The M optical signals along with the M inverted optical signals are then applied to the multiplexer, which provides an optical wavelength division multiplexed (WDM) signal having 2M channels.

公开(公告)号：US06987752B1

公开(公告)日：2006-01-17

申请号：US09396055

申请日：1999-09-15

申请人： Mohsen Sarraf ,  Mohammad Hossein Zarrabizadeh

发明人： Mohsen Sarraf ,  Mohammad Hossein Zarrabizadeh

IPC分类号： H04J1/00

CPC分类号： H04L27/2657 ,  H04L27/2613 ,  H04L27/2675

摘要： A method and apparatus are disclosed for frequency offset estimation and interleaver synchronization, using periodic signature sequences, such as Barker codes. The periodic signature sequence is used for interleaver synchronization or frequency offset estimation or both. The periodic signature sequence is transmitted over a certain number of bins in both the upper and lower sides of the DAB signal. Since the signature sequences are assigned to specific bins known to the receiver, any shift of the correlated peak from the expected location due to frequency offset errors can be estimated by the frequency offset algorithm. If the Barker sequence is placed, for example, in the last column of the DAB interleaver, the location of the Barker sequence upon correlation of the received digital signal identifies the beginning of an interleaver block. A Barker sequence is transmitted over a signature frame every L data frames on each side band, where L is generally the number of OFDM frames that can fill the interleaver memory. If the maximum frequency offset is M, then the frequency offset algorithm utilizes a search window of size n+2M (between bins N−M through N+n+M), and attempts to maintain the Barker sequence in the center of the search window. At the receiver, the Barker sequence is mapped to the OFDM signature bins that do not belong to uncertainty regions (the group of bins that can fall out of the receiver processing range for maximum positive and negative frequency offset values). Thus, the Barker sequence bins are processed by the disclosed receiver as long as the frequency offset does not exceed the specified maximum frequency offset.

摘要翻译： 公开了一种用于频偏估计和交织器同步的方法和装置，其使用诸如巴克码之类的周期签名序列。 周期性签名序列用于交织器同步或频偏估计或两者。 周期性签名序列在DAB信号的上侧和下侧的一定数量的箱上传输。 由于签名序列被分配给接收器已知的特定信息组，所以可以通过频率偏移算法来估计相关峰值与预期位置之间由于频率偏移误差的偏移。 如果Barker序列例如放置在DAB交织器的最后一列中，则在接收到的数字信号相关时，Barker序列的位置标识交织器块的开始。 Barker序列在每个边带上的每L个数据帧上通过签名帧发送，其中L通常是可以填充交织器存储器的OFDM帧的数量。 如果最大频率偏移为M，则频率补偿算法利用大小为n + 2M（在N-M到N + n + M之间）的搜索窗口，并尝试将Barker序列保持在搜索窗口的中心。 在接收机处，Barker序列被映射到不属于不确定区域的OFDM签名箱（对于最大正和负频率偏移值可能落在接收机处理范围之外的组的组）。 因此，只要频率偏移不超过指定的最大频率偏移量，则所公开的接收机处理Barker序列箱。

公开(公告)号：US06928046B1

公开(公告)日：2005-08-09

申请号：US09304830

申请日：1999-05-05

申请人： Masoud Sajadieh ,  Mohsen Sarraf ,  Mohammad Hossein Zarrabizadeh

发明人： Masoud Sajadieh ,  Mohsen Sarraf ,  Mohammad Hossein Zarrabizadeh

IPC分类号： H03K9/00 ,  H04H20/88 ,  H04J11/00 ,  H04L27/26 ,  H04L27/28 ,  H04H5/00

CPC分类号： H04L27/2656 ,  H04L27/2678

摘要： Frame synchronization of a received OFDM signal (such as that used in a hybrid FM DAB system) is provided by filtering out significant outer frequency portions of the digital channels, and then using cyclic extension and correlation of the cyclically extended bits (or samples). The received OFDM signal is passed through a bandpass filter to remove outer digital subcarriers (i.e., those farthest from a center frequency) from a received OFDM signal before correlating to locate the OFDM frame boundaries. By filtering out digital subcarriers within each of the digital channels, particularly those closest to adjacent channels and thus most likely to be interfered with by an adjacent first channel OFDM (or FM) signal, correlation between cyclically extended bit (or sample) patterns and thus frame synchronization of OFDM signals can be improved significantly.

摘要翻译： 通过滤出数字信道的重要外频部分，然后使用循环扩展比特（或采样）的循环扩展和相关来提供接收的OFDM信号（例如在混合FM DAB系统中使用的OFDM信号）的帧同步。 所接收的OFDM信号通过带通滤波器以在相关之前从接收的OFDM信号中去除外部数字子载波（即，离中心频率最远的那些），以定位OFDM帧边界。 通过滤除每个数字信道内的数字子载波，特别是那些最接近相邻信道的数字子载波，从而最可能被相邻第一信道OFDM（或FM）信号干扰，循环扩展位（或采样）模式之间的相关性因此 可以显着提高OFDM信号的帧同步。

公开(公告)号：US06842421B1

公开(公告)日：2005-01-11

申请号：US09398500

申请日：1999-09-17

申请人： Mohsen Sarraf ,  Mohammad Hossein Zarrabizadeh

发明人： Mohsen Sarraf ,  Mohammad Hossein Zarrabizadeh

IPC分类号： H04B7/08 ,  H04J11/00 ,  H04L27/26

CPC分类号： H04B7/0894 ,  H04B7/0857 ,  H04L27/2602 ,  H04L27/2647

摘要： A novel antenna diversity technique for OFDM receivers is disclosed. A method and apparatus are disclosed for combining in the frequency domain the various signals received on each of the multiple antennas in an OFDM communication system. At the OFDM transmitter, the transmitted signal is differentially encoded over frequency, as opposed to time, to differentially encode the transmitted signal in the frequency domain with respect to consecutive bins (OFDM sub-carriers). The OFDM receiver processes a signal received on a number of diversity branches and combines the received signals using a post-detection combining technique after differential decoding. Each frame is independently processed by a differential decoder and then delayed to align each symbol in a given frame. The post-detection combining of the frame data inherently scales the received samples and thereby implements an optimal maximum ratio combining mechanism. Unlike conventional maximum ratio combining techniques, the faded bins are scaled individually by the differential decoder, based on their own power levels rather than the overall power of the OFDM frame. Thus, bins with higher magnitudes will be weighted more heavily than bins having severe channel fading.

摘要翻译： 公开了一种用于OFDM接收机的新型天线分集技术。 公开了一种用于在频域中组合在OFDM通信系统中在多个天线中的每一个上接收的各种信号的方法和装置。 在OFDM发射机处，与时间相反，所发送的信号在频率上进行差分编码，从而相对于连续的载波（OFDM子载波）差分编码频域中的发射信号。 OFDM接收器处理在多个分集分支上接收的信号，并且在差分解码之后使用检测后组合技术组合接收的信号。 每个帧由差分解码器独立地处理，然后被延迟以在给定帧中对准每个符号。 帧数据的后检测组合固有地缩放所接收的样本，从而实现最佳最大比组合机制。 与传统的最大比组合技术不同，衰减的箱体由差分解码器基于它们自己的功率级而不是OFDM帧的整体功率单独地缩放。 因此，具有较高幅度的箱体将比具有严重的通道衰落的箱子更加重。

公开(公告)号：US06747948B1

公开(公告)日：2004-06-08

申请号：US09371902

申请日：1999-08-11

申请人： Mohsen Sarraf ,  Mohammed Zarrabizadeh

发明人： Mohsen Sarraf ,  Mohammed Zarrabizadeh

IPC分类号： H04J1100

CPC分类号： H04L1/0071 ,  H04L5/023 ,  H04L27/2602 ,  H04L27/2626 ,  H04L27/2647

摘要： A transmission system encodes blocks of source data with error correction codes and spreads encoded data for each source block over a range of time and frequencies. This has the effect of reducing the impact of flat fading. This is because if a portion of the encoded data corresponding to a block of source data is lost, as a result of flat fading during a time interval, other portions, transmitted at a different time, may not be affected. A receiving system may therefore recover the original block of source data based on the portions of the encoded data that were received, including error correction bits. The transmission and receiving systems may be orthogonal frequency division multiplexed (OFDM) communications systems.

摘要翻译： 传输系统利用纠错码对源数据块进行编码，并在时间和频率的范围内扩展每个源块的编码数据。 这具有减少平坦褪色的影响的作用。 这是因为如果与源数据块对应的编码数据的一部分丢失，则作为在时间间隔期间的平坦衰落的结果，可能不会影响在不同时间发送的其他部分。 因此，接收系统可以基于接收到的编码数据的部分恢复原始数据块，包括纠错位。 发射和接收系统可以是正交频分复用（OFDM）通信系统。