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1.发明申请公开(公告)号：US20050163236A1
公开(公告)日：2005-07-28
申请号：US10990143
申请日：2004-11-16
CPC分类号： H04L1/06 , H04B7/0671
摘要： A method and apparatus are disclosed for transmitting symbols in a multiple antenna communication system. The disclosed frame structure comprises a preamble having a plurality of long training symbols that are transmitted on a plurality transmit antennas. At least a portion of the frame is delayed on at least one transmit antenna. The disclosed frame formats of the present invention are backwards compatible to existing single antenna communication systems. The delay amount, D, can be approximately equal to one OFDM time sample period, T. The delayed version can be obtained by introducing a time delay into a signal on the delayed branch(es) or by cyclically shifting at least a portion of each frame on the delayed branch(es). The entire frame or only the preamble portion of each frame can be delayed.
摘要翻译： 公开了用于在多天线通信系统中发送符号的方法和装置。 所公开的帧结构包括具有在多个发射天线上发射的多个长训练符号的前同步码。 帧的至少一部分在至少一个发射天线上被延迟。 所公开的本发明的帧格式向后兼容于现有的单一天线通信系统。 延迟量D可以近似等于一个OFDM时间采样周期T.延迟版本可以通过在延迟分支上的信号中引入时间延迟或者通过周期性地移位每个 在延迟分支上的框架。 每个帧的整个帧或仅前导码部分可以被延迟。
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2.发明申请Methods and apparatus for backwards compatible communication in a multiple antenna communication system using time orthogonal symbols 有权在使用时间正交符号的多天线通信系统中用于向后兼容通信的方法和装置公开(公告)号：US20060251193A1
公开(公告)日：2006-11-09
申请号：US10562620
申请日：2004-06-30
申请人： Robert Kopmeiners , Tim Schenk , Allert Zelst
发明人： Robert Kopmeiners , Tim Schenk , Allert Zelst
IPC分类号： H04B1/02
CPC分类号： H04L5/0023 , H04B7/0413 , H04B7/0684 , H04L1/06 , H04L5/0048 , H04L25/0204 , H04L25/0206 , H04L25/0226 , H04L27/2613
摘要： A method and apparatus are disclosed for transmitting symbols in a multiple antenna communication system according to a frame structure, such that the symbols can be interpreted by a lower order receiver (i.e., a receiver having a fewer number of (antennas than the transmitter). The disclosed frame structure comprises a legacy preamble having at least one long training symbol and N-1 additional long training symbols that are transmitted on each of N transmit antennas. The legacy preamble may be, for Q example, an 802.11 a/g preamble that includes at least one short training symbol, at least one long training symbol and at least one SIGNAL field. A sequence of each of the long training symbols on each of the N transmit antennas are time orthogonal. The long training symbols can be time orthogonal by introducing a phase shift to each of long training symbols relative to one another.
摘要翻译： 公开了一种用于根据帧结构在多天线通信系统中发送符号的方法和装置，使得符号可以由较低阶接收机（即，具有较少数量（接收天线的发射机）的接收机）来解释。 公开的帧结构包括具有至少一个长训练符号和在N个发射天线中的每一个上发射的N-1个附加长训练符号的传统前导码。对于Q示例，传统前导码可以是802.11a / g前导码， 包括至少一个短训练符号，至少一个长训练符号和至少一个信号字段，每个N个发射天线中每个长训练符号的序列是时间正交的，长训练符号可以通过 对相对于彼此的长训练符号引入相移。
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3.发明申请Method and apparatus for detecting a collision in a carrier sense multiple access wireless system 有权用于检测载波侦听多址无线系统中的冲突的方法和装置公开(公告)号：US20050068979A1
公开(公告)日：2005-03-31
申请号：US10672657
申请日：2003-09-26
CPC分类号： H04L27/0012 , H04L27/2647 , H04W74/0825
摘要： A method and apparatus are disclosed for detecting a collision in a carrier sense multiple access wireless communication system. Each transmitting station includes a collision detector that evaluates one or more predefined criteria to determine when a collision has occurred. The collision detector evaluates the measured energy level and optionally payload and/or preamble detection information to determine if a collision has occurred. A collision occurred when an expected ACK message is not received, in the presence of an increased energy level and possibly preamble or payload detection information. The collision detector of the present invention can be activated, for example, at a time corresponding to the start of the 802.11 Short Inter Frame Space interval.
摘要翻译： 公开了用于检测载波侦听多址无线通信系统中的冲突的方法和装置。 每个发射站包括一个碰撞检测器，该碰撞检测器评估一个或多个预定标准以确定碰撞发生的时间。 碰撞检测器评估所测量的能级，以及可选的有效载荷和/或前导码检测信息，以确定是否发生了冲突。 在存在增加的能级和可能的前导码或有效载荷检测信息的情况下，当未接收到期望的ACK消息时发生冲突。 本发明的碰撞检测器例如可以在对应于802.11短帧间隔间隔的开始的时间被激活。
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4.发明申请公开(公告)号：US20080069274A1
公开(公告)日：2008-03-20
申请号：US11946152
申请日：2007-11-28
申请人： Robert Kopmeiners , Didier Van Nee
发明人： Robert Kopmeiners , Didier Van Nee
IPC分类号： H04L1/00
CPC分类号： H04L25/03146 , H04L2025/03401 , H04L2025/0342 , H04L2025/0349 , H04L2025/0377
摘要： The invention relates to a detection method using a receiver of a digital communication system for the detection of a symbol from a received signal, which signal is transmitted by a transmitter of the digital communication system, wherein the symbol is a selected symbol out of a predetermined set of symbols and wherein each symbol of the predetermined set comprises a sequence of chips wherein each of the chips is PSK-modulated according to a selected modulation code
摘要翻译： 本发明涉及一种使用数字通信系统的接收机的检测方法，用于从接收信号检测符号，该信号由数字通信系统的发射机传输，其中该符号是预定的 一组符号，并且其中预定集合的每个符号包括码片序列，其中每个码片根据选择的调制码进行PSK调制
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5.发明申请Method and apparatus for estimating DC offset in an orthogonal frequency division multiplexing system 有权用于估计正交频分复用系统中的直流偏移的方法和装置公开(公告)号：US20050111525A1
公开(公告)日：2005-05-26
申请号：US10918223
申请日：2004-08-13
申请人： Bas Driesen , Joseph Havens , Robert Kopmeiners
发明人： Bas Driesen , Joseph Havens , Robert Kopmeiners
CPC分类号： H04L25/061 , H04L25/0202 , H04L27/2647
摘要： Methods and apparatus are disclosed for DC offset estimation and for DC offset compensation that collectively reduce or eliminate the distortion of subcarriers due to DC offset in an OFDM receiver. The DC offset estimation is obtained by subtracting a sum of time domain samples of an OFDM symbol for two consecutive OFDM symbols or subtracting a known transmitted OFDM symbol and a frequency domain representation of a received version of the known OFDM symbol (at least one of which is adjusted to compensate for channel distortion). The DC offset compensation is accomplished by removing the estimated DC offset from the received signal. The DC estimation process and the DC compensation process can be connected in disclosed feed-forward or feedback configurations.
摘要翻译： 公开了用于DC偏移估计和DC偏移补偿的方法和装置，其共同地减少或消除由于OFDM接收机中的DC偏移引起的子载波的失真。 通过减去两个连续的OFDM符号的OFDM符号的时域采样的和，或者减去已知的发射的OFDM符号和已知OFDM符号的接收版本的频域表示（其中至少一个 被调整以补偿信道失真）。 通过从接收到的信号中去除估计的直流偏移来实现DC偏移补偿。 DC估计过程和DC补偿过程可以在公开的前馈或反馈配置中连接。
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