公开(公告)号：US08331217B2

公开(公告)日：2012-12-11

申请号：US12412607

申请日：2009-03-27

申请人： Samel Celebi ,  Jie Song ,  Paul M. Yun

发明人： Samel Celebi ,  Jie Song ,  Paul M. Yun

IPC分类号： H04B1/00 ,  H04J11/00

CPC分类号： H04B7/0682 ,  H04B7/0671 ,  H04B7/18517 ,  H04W52/34

摘要： A ground- or roof-top-based repeater in an OFDM system uses multiple transmission antennas to transmit multiple identical OFDM signals. Dithering is performed by introducing a slight variable-frequency phase offset to all but one of the multiple identical transmitted OFDM signals. The effective overall channel is more dynamic and provides spatial diversity to minimize long periods of fading in fading subchannels of the OFDM signals when the receiver is in a slow moving or stationary situation. To overcome the additional cancellation problem that can occur when two or more of the transmitting antennas are (i) in a line-of-site position with the receiver and (ii) approximately the same distance from the receiver, a delay is deliberately introduced to make the delayed signals appear to be reflected signals. This delay will not negatively impact the OFDM receiver performance as long as the delay is within the guard interval used in the OFDM process.

摘要翻译： OFDM系统中的基于地面或屋顶的中继器使用多个发射天线来传输多个相同的OFDM信号。 通过对多个相同的发射OFDM信号中的一个引入轻微的可变频率相位偏移来执行抖动。 有效整体信道更为动态，并且当接收机处于缓慢移动或静止状态时，提供空间分集以最小化OFDM信号的衰落子信道中的衰落长时间衰落。 为了克服当两个或多个发射天线（i）处于与接收机的现场位置和（ii）与接收机大致相同的距离）时可能发生的附加消除问题，故意延迟延迟到 使延迟信号看起来是反射信号。 只要延迟在OFDM过程中使用的保护间隔内，该延迟不会对OFDM接收机性能产生负面影响。

公开(公告)号：US07529177B2

公开(公告)日：2009-05-05

申请号：US10229673

申请日：2002-08-28

申请人： Samel Celebi ,  Jie Song ,  Paul M. Yun

发明人： Samel Celebi ,  Jie Song ,  Paul M. Yun

IPC分类号： H04B1/00 ,  H04J11/00

CPC分类号： H04B7/0682 ,  H04B7/0671 ,  H04B7/18517 ,  H04W52/34

摘要： A ground-or roof-top-based repeater in an OFDM system uses multiple transmission antennas to retransmit satellite signals. By using multiple transmission antennas, multiple identical OFDM signals are transmitted. Dithering is performed by, using a phase of Rayleigh process generator, introducing a slight variable-frequency phase offset to all but one of the multiple identical transmitted OFDM signals, and thus the effective overall channel is more dynamic and provides spatial diversity to minimize long periods of fading in fading subchannels of the OFDM signals when the receiver is in a slow moving or stationary situation. To overcome the additional cancellation problem that can occur when two or more of the transmitting antennas are in a line-of-site position with the receiver and approximately the same distance from the receiver, a delay is deliberately introduced to make the delayed signal(s) appear to be reflected signals. This delay will not negatively impact the OFDM receiver performance as long as the delay is within the guard interval used in the OFDM process.

摘要翻译： OFDM系统中的基于地面或屋顶的中继器使用多个发射天线来重发卫星信号。 通过使用多个发送天线，发送多个相同的OFDM信号。 通过使用瑞利处理发生器的相位对多个相同发射的OFDM信号中的除了一个之外的所有发射的OFDM信号引入轻微的可变频率相位偏移来进行抖动，因此有效整体信道更加动态，并提供空间分集以最小化长周期 当接收机处于缓慢移动或静止状态时，OFDM信号的衰落子信道中的衰落。 为了克服当两个或多个发射天线处于与接收机的位置位置并且与接收机大致相同距离时可能发生的额外的消除问题，故意引入延迟以使延迟的信号 ）似乎是反射信号。 只要延迟在OFDM过程中使用的保护间隔内，该延迟不会对OFDM接收机性能产生负面影响。

公开(公告)号：US20090180564A1

公开(公告)日：2009-07-16

申请号：US12412607

申请日：2009-03-27

申请人： Samel Celebi ,  Jie Song ,  Paul M. Yun

发明人： Samel Celebi ,  Jie Song ,  Paul M. Yun

IPC分类号： H04J11/00 ,  H04L27/28

CPC分类号： H04B7/0682 ,  H04B7/0671 ,  H04B7/18517 ,  H04W52/34

摘要： A ground- or roof-top-based repeater in an OFDM system uses multiple transmission antennas to transmit multiple identical OFDM signals. Dithering is performed by introducing a slight variable-frequency phase offset to all but one of the multiple identical transmitted OFDM signals. The effective overall channel is more dynamic and provides spatial diversity to minimize long periods of fading in fading subchannels of the OFDM signals when the receiver is in a slow moving or stationary situation. To overcome the additional cancellation problem that can occur when two or more of the transmitting antennas are (i) in a line-of-site position with the receiver and (ii) approximately the same distance from the receiver, a delay is deliberately introduced to make the delayed signals appear to be reflected signals. This delay will not negatively impact the OFDM receiver performance as long as the delay is within the guard interval used in the OFDM process.

摘要翻译： OFDM系统中的基于地面或屋顶的中继器使用多个发射天线来传输多个相同的OFDM信号。 通过对多个相同的发射OFDM信号中的一个引入轻微的可变频率相位偏移来执行抖动。 有效整体信道更为动态，并且当接收机处于缓慢移动或静止状态时，提供空间分集以最小化OFDM信号的衰落子信道中的衰落长时间衰落。 为了克服当两个或多个发射天线（i）处于与接收机的现场位置和（ii）与接收机大致相同的距离）时可能发生的附加消除问题，故意延迟延迟到 使延迟信号看起来是反射信号。 只要延迟在OFDM过程中使用的保护间隔内，该延迟不会对OFDM接收机性能产生负面影响。

公开(公告)号：US4769777A

公开(公告)日：1988-09-06

申请号：US878254

申请日：1986-06-25

申请人： William D. Bittle ,  Ellwood P. McGrogan ,  Moishe Kleidermacher ,  Paul M. Yun

发明人： William D. Bittle ,  Ellwood P. McGrogan ,  Moishe Kleidermacher ,  Paul M. Yun

IPC分类号： H03K3/84 ,  G06F1/02

CPC分类号： H03K3/84

摘要： An apparatus for breaking the periodicity of the pseudorandom bit stream output from a linear sequence generator. The apparatus includes a ring oscillator which periodically corrupts the sequence of the generator. The level of the supply voltage applied to the logic elements of the ring oscillator is varied over time, thereby altering the oscillator output frequency. In a second embodiment, the temperature of the logic elements of the ring oscillator is varied over time, thereby also altering the oscillator output frequency. A system comprising four of the above-disclosed apparatus having different linear sequences and different corrupting influences, are multiplexed, wherein the multiplexing selection criterion is determined by a logical combination of the four linear sequences.

摘要翻译： 一种用于破坏从线性序列发生器输出的伪随机比特流的周期性的装置。 该装置包括周期性地破坏发生器序列的环形振荡器。 施加到环形振荡器的逻辑元件的电源电压的电平随时间变化，从而改变振荡器的输出频率。 在第二实施例中，环形振荡器的逻辑元件的温度随时间变化，从而也改变了振荡器的输出频率。 包括四个具有不同线性序列和不同腐蚀影响的上述公开装置的系统被多路复用，其中多路复用选择标准由四个线性序列的逻辑组合确定。