Detecting the number of transmit antennas in wireless communication systems
    1.
    发明申请
    Detecting the number of transmit antennas in wireless communication systems 有权
    检测无线通信系统中发射天线的数量

    公开(公告)号:US20050271157A1

    公开(公告)日:2005-12-08

    申请号:US11139925

    申请日:2005-05-27

    摘要: To detect the number of transmit antennas, a fast Fourier transform operation is performed on the received samples of the transmitted long training symbols of a preamble. Next, each of the Fourier transformed results is multiplied with the reference frequency-domain representation of the long training symbol so as to remove the effect of the symbols and to maintain the channel information. Next, inverse Fourier transform or least squares operations is performed on the multiplied values to compute channel impulse response. The number of shifted impulse response in the channel impulse response represents the detected number of transmit antennas. Packets containing preambles of the present invention may be received by extended devices as well as by legacy receivers that are not configured to receive and interpret these preambles. The training symbols may be cyclically-shifted and transmitted on different transmit antennas.

    摘要翻译: 为了检测发送天线的数量,对前导码的发送的长训练符号的接收样本执行快速傅里叶变换操作。 接下来,将每个傅立叶变换结果乘以长训练符号的参考频域表示,以便消除符号的影响并维持频道信息。 接下来,对乘法值执行逆傅里叶变换或最小二乘法运算以计算信道脉冲响应。 信道脉冲响应中移位脉冲响应的数量表示检测到的发射天线数。 包含本发明的前导码的分组可以由扩展设备以及未被配置为接收和解释这些前同步码的传统接收机来接收。 训练符号可以循环移位并在不同的发射天线上发射。

    Wireless messaging preambles allowing for beamforming and legacy device coexistence

    公开(公告)号:US20060193340A1

    公开(公告)日:2006-08-31

    申请号:US11351279

    申请日:2006-02-08

    IPC分类号: H04J3/22 H04J3/16 H04B7/00

    摘要: A modified preamble is used by extended devices that operate in mixed mode environments and green field environments, to accommodate beamforming of transmissions. In one process, an extended wireless device processes data for transmission of that data as a packet, wherein the extended wireless device is a device configured to communicate using a standard protocol understood by each node device and an extended protocol not understood by legacy node devices. If the packet is to be directed at an extended device, the extended wireless device sends a preamble of that packet that is usable in an extended mode at extended devices and usable at a receiving legacy device to determine that the receiving legacy device is not the destination of data to follow the preamble. Once the receiving legacy device is expected to be deferring the network, the extended wireless device can beamform its signal or otherwise vary from the legacy protocol in communications with extended devices.

    Modified preamble structure for IEEE 802.11a extensions to allow for coexistence and interoperability between 802.11a devices and higher data rate, MIMO or otherwise extended devices
    3.
    发明申请
    Modified preamble structure for IEEE 802.11a extensions to allow for coexistence and interoperability between 802.11a devices and higher data rate, MIMO or otherwise extended devices 有权
    用于IEEE 802.11a扩展的修改的前导码结构,以允许802.11a设备和更高数据速率,MIMO或其他扩展设备之间的共存和互操作性

    公开(公告)号:US20050286474A1

    公开(公告)日:2005-12-29

    申请号:US11140349

    申请日:2005-05-27

    摘要: A modified preamble is used by extended devices that operate at higher rates, MIMO or other extensions relative to strict 802.11a-compliant devices. The extended devices might use multiple antenna techniques (MIMO), where multiple data streams are multiplexed spatially and/or multi-channel techniques, where an extended transmitter transmits using more than one 802.11a channel at a time. Such extensions to IEEE 802.11a can exist in extended devices. The modified preamble is usable for signaling, to legacy devices as well as extended devices, to indicate capabilities and to cause legacy devices or extended devices to defer to other devices such that the common communication channel is not subject to unnecessary interference. The modified preamble is also usable for obtaining MIMO channel estimates and/or multi-channel estimates. The modified preamble preferably includes properties that facilitate detection of conventional and/or extended modes (“mode detection”) and provides some level of coexistence with legacy IEEE 802.11 a devices.

    摘要翻译: 经修改的前同步码由相对于严格的符合802.11a标准的设备的较高速率,MIMO或其他扩展操作的扩展设备使用。 扩展设备可能使用多个天线技术(MIMO),其中多个数据流在空间和/或多信道技术上复用,其中扩展发射机一次使用多于一个802.11a信道进行发射。 IEEE 802.11a的这种扩展可以存在于扩展设备中。 经修改的前导码可用于对传统设备以及扩展设备进行信令,以指示能力并使遗留设备或扩展设备推迟到其他设备,使得公共通信信道不受不必要的干扰。 经修改的前导码也可用于获得MIMO信道估计和/或多信道估计。 经修改的前导码优选地包括便于检测常规和/或扩展模式(“模式检测”)并且提供与传统IEEE 802.11的设备的一些级别的性质的属性。

    ADVANCED WIRELESS PACKET TRANSMISSION SCHEME WITH ENHANCEMENTS TO ACCOMMODATE BASIC WIRELESS PACKET TRANSMISSION SCHEME
    4.
    发明申请
    ADVANCED WIRELESS PACKET TRANSMISSION SCHEME WITH ENHANCEMENTS TO ACCOMMODATE BASIC WIRELESS PACKET TRANSMISSION SCHEME 有权
    高级无线分组传输方案,增强基本无线分组传输方案

    公开(公告)号:US20070207823A1

    公开(公告)日:2007-09-06

    申请号:US11681531

    申请日:2007-03-02

    IPC分类号: H04Q7/20

    摘要: Methods and systems for signaling on a mixed-mode wireless network comprising a plurality of channels are provided. The mixed-mode wireless network includes high-throughput (HT) wireless devices and legacy wireless devices that use channels of the same width. The HT devices transmit data on at least two channels, while the legacy devices transmit on one channel. The distances between the HT channels and the distances between the legacy channels might differ, however, the channels used by the HT devices and the legacy devices may overlap. As a result, cooperation between the HT devices and legacy devices is provided to enable the devices to coexist on the same wireless network by minimizing collisions and interference. The HT devices are configured to send control information to the legacy devices to coordinate transmission by the HT devices with the legacy devices.

    摘要翻译: 提供了在包括多个通道的混合模式无线网络上进行信令的方法和系统。 混合模式无线网络包括高吞吐量(HT)无线设备和使用相同宽度的信道的传统无线设备。 HT设备在至少两个通道上传输数据,而传统设备在一个通道上传输数据。 HT信道之间的距离和传统信道之间的距离可能不同,但HT设备和传统设备使用的信道可能会重叠。 结果,提供HT设备和传统设备之间的协作,以使设备能够通过最小化冲突和干扰来在同一无线网络上共存。 HT设备被配置为向旧设备发送控制信息,以协调HT设备与传统设备的传输。

    Adaptive packet detection for detecting packets in a wireless medium
    5.
    发明申请
    Adaptive packet detection for detecting packets in a wireless medium 有权
    用于检测无线介质中的分组的自适应分组检测

    公开(公告)号:US20050190786A1

    公开(公告)日:2005-09-01

    申请号:US11064761

    申请日:2005-02-22

    摘要: In a packet detector, one or more tests are performed for packet detection according to packet detection parameters associated with the one or more tests, a rate of false detection is measured, and the packet detection parameters are adjusted accordingly to reduce the rate of false detection. The rate of false detection might be determined by analyzing post-detection and processing of a signal deemed to be a signal representing a packet for a failure of decoding indicative of a false detection. Such analysis might include testing for a failed SFD search, training symbol anomalies, poor conditioning of metrics used to determine frequency offset and OFDM timing, incorrect data fields, or the like.

    摘要翻译: 在分组检测器中,根据与一个或多个测试相关联的分组检测参数,对分组检测执行一个或多个测试,测量错误检测率,并相应地调整分组检测参数以降低错误检测率 。 可以通过分析被认为是表示用于指示错误检测的解码失败的分组的信号的信号的后检测和处理来确定错误检测的速率。 这种分析可能包括测试失败的SFD搜索,训练符号异常,用于确定频率偏移和OFDM定时的度量的不良调节,不正确的数据字段等。

    Pilot tones in a multi-transmit OFDM system usable to capture transmitter diversity benefits
    6.
    发明申请
    Pilot tones in a multi-transmit OFDM system usable to capture transmitter diversity benefits 有权
    可用于捕获发射机分集优势的多发射OFDM系统中的导频音调

    公开(公告)号:US20060018394A1

    公开(公告)日:2006-01-26

    申请号:US11187603

    申请日:2005-07-21

    IPC分类号: H04K1/10

    摘要: In a wireless transmitter having a plurality of spatial streams differentiable at a receiver, wherein data is encoded and transmitted over a communication channel with pilot tones to provide the receiver with information about the effects of the communication channel and/or transmitter impairments and/or receiver impairments on the spatial streams transmitted, the benefits can be provided by identifying a plurality of symbol periods within which symbols representing some of the encoded data are to be transmitted, identifying pilot tone values for the plurality of symbol periods, wherein the identified pilot tone values are such that the receiver, when receiving at least some of the pilot tones having the identified pilot tone values, is provided with signals enabling the receiver to characterize the communication channel and/or transmitter impairments and/or receiver impairments to obtain transmit stream diversity gain, and transmitting the symbols and the pilot tones over the plurality of spatial streams for the plurality of symbol periods. In some embodiments, the pilot tones are orthogonal over space and time or over space and time and frequency, while in others they are semi-orthogonal. Pilot tone values might be of a constant amplitude and phase shifted, or might also have amplitude variations wherein at least two pilot tones are nonzero for spatial streams for a given symbol period.

    摘要翻译: 在具有在接收机可微分的多个空间流的无线发射机中,其中通过具有导频音调的通信信道对数据进行编码和发送,以向接收机提供关于通信信道和/或发射机损伤和/或接收机的影响的信息 对发送的空间流的损伤,可以通过识别多个符号周期来提供益处,在多个符号周期内将表示一些编码数据的符号发送,识别多个符号周期的导频音值,其中所识别的导频音调值 使得接收机在接收到具有所识别的导频音值的至少一些导频音时,被提供有使得接收机能够表征通信信道和/或发射机损伤和/或接收机损伤以获得发射流分集增益的信号 并且通过多个传输符号和导频音调 的多个符号周期的空间流。 在一些实施例中,导频音调在空间和时间上或在空间和时间和频率上是正交的,而在另一些实施例中,它们是半正交的。 导频音调值可能具有恒定幅度和相移,或者也可能具有振幅变化,其中对于给定符号周期,空间流的至少两个导频音调不为零。

    Wide frequency offset correction using encoded interburst phase differences
    7.
    发明申请
    Wide frequency offset correction using encoded interburst phase differences 有权
    使用编码的突发相位差进行宽频偏校正

    公开(公告)号:US20050175114A1

    公开(公告)日:2005-08-11

    申请号:US11101029

    申请日:2005-04-06

    IPC分类号: H04B7/216 H04K1/10 H04L27/26

    摘要: Systems and methods for wide frequency offset synchronization are provided. A synchronization data sequence is encoded onto a series of OFDM frequency domain bursts as interburst phase differences between training symbols included within the successive bursts. The interburst phase differences may also encode system configuration information. This technique may be used in conjunction with other synchronization techniques to greatly extend the frequency acquisition range achievable with low cost analog components.

    摘要翻译: 提供了宽频偏同步的系统和方法。 同步数据序列被编码到一系列OFDM频域突发上,作为包括在连续脉冲串内的训练符号之间的突发间相位差。 突发相位差也可以编码系统配置信息。 该技术可以与其他同步技术结合使用,以大大扩展用低成本模拟组件实现的频率采集范围。

    Packet concatenation in wireless networks
    9.
    发明申请
    Packet concatenation in wireless networks 有权
    无线网络中的数据包连接

    公开(公告)号:US20050237992A1

    公开(公告)日:2005-10-27

    申请号:US11107386

    申请日:2005-04-15

    IPC分类号: H04L12/28 H04L12/56 H04L29/06

    摘要: A wireless network includes a transmitting device and a plurality of receiving devices. The transmitting device is configured to receive a plurality of data packets, including a first data packet and a second data packet, prepare a preamble, prepare a signal field for each of the plurality of data packets, including a first signal field based on the first data packet and a second signal field based on the second data packet, and broadcast the preamble, the first signal field, the first data packet, the second signal field, and the second data packet as a concatenated packet.

    摘要翻译: 无线网络包括发送设备和多个接收设备。 所述发送装置被配置为接收包括第一数据分组和第二数据分组的多个数据分组,准备前同步码,为所述多个数据分组中的每一个准备信号字段,所述信号字段包括基于所述第一数据分组的第一信号字段 数据分组和基于第二数据分组的第二信号字段,并且作为级联分组广播前导码,第一信号字段,第一数据分组,第二信号字段和第二数据分组。