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101. 发明授权

US5946625A Method for improving co-channel interference in a cellular system 失效
标题翻译：用于改善蜂窝系统中的同信道干扰的方法
公开(公告)号：US5946625A
公开(公告)日：1999-08-31
申请号：US728564
申请日：1996-10-10
申请人： Amer Hassan , Stanley L. Reinhold , Rajaram Ramesh
发明人： Amer Hassan , Stanley L. Reinhold , Rajaram Ramesh
IPC分类号： H04B7/26 , H04W16/02 , H04W16/12 , H04Q7/36 , H04B7/185
CPC分类号： H04W16/12 , H04B7/2621 , H04W16/02
摘要： A fractional loading scheme is used to improve the spectral efficiency of a cellular system, and therefore increase the number of users that the system can support. The fractional loading scheme allows only a fraction of the total number of available communication channels within each cell to be used simultaneously. Thus, each cell is deliberately underloaded to operate at less than its full capacity. The underloading of the individual cells reduces the spectral efficiency within each cell. However, the underloading of each cell means that there will be fewer interfering users at any given time so that the co-channel interference is reduced. This reduction in co-channel interference allows the reuse distance between co-channel cells to be reduced thereby increasing the reuse of frequencies throughout the system resulting in an increase in spectral efficiency in the system as a whole.
摘要翻译：分数加载方案用于提高蜂窝系统的频谱效率，因此增加了系统可以支持的用户数量。分数加载方案仅允许同时使用每个单元内的可用通信信道总数的一部分。因此，每个电池故意负载低于其全部容量运行。单个单元的欠载降低了每个单元内的频谱效率。然而，每个小区的欠载意味着在任何给定时间将存在较少的干扰用户，使得减少同信道干扰。同信道干扰的这种减少允许减少同信道小区之间的重用距离，从而增加整个系统中频率的重用，导致整个系统中频谱效率的提高。

102. 发明授权

US5889827A Method and apparatus for digital symbol detection using medium response estimates 失效
公开(公告)号：US5889827A
公开(公告)日：1999-03-30
申请号：US766167
申请日：1996-12-12
申请人： Gregory E. Bottomley , Karl Molnar , Rajaram Ramesh
发明人： Gregory E. Bottomley , Karl Molnar , Rajaram Ramesh
IPC分类号： H04B1/707 , H04B3/04 , H04B3/06 , H04B7/005 , H04L25/02 , H04L25/03 , H04B1/10
CPC分类号： H04B1/707 , H04B7/005 , H04L25/0202 , H04L25/03178 , H04L25/03299
摘要： According to the present invention, the effects of the transmission medium on transmitted information symbols are estimated separately from other effects, e.g., those associated with receive and transmit filters, using knowledge of the pulse shaping. The medium response estimate is then used to detect information symbols. Previously, receivers had used estimates of the composite channel to detect symbols. This, however, assumed uncorrelated noise, which is not always the case.

103. 发明授权

US5796780A Coherent modulation of CPM signals 失效
标题翻译： CPM信号的相干调制
公开(公告)号：US5796780A
公开(公告)日：1998-08-18
申请号：US599011
申请日：1996-02-09
申请人： Rajaram Ramesh
发明人： Rajaram Ramesh
IPC分类号： H04L25/03 , H04L27/20 , H04L27/10 , H04L27/12 , H04L27/14
CPC分类号： H04L27/2003 , H04L25/03866 , H04L27/2017
摘要： Coherent modulation schemes for CPM signals. The disclosed schemes avoid the error probability increase due to the differential encoding by using a coherent encoder. A simple demodulator can be implemented by using a Nyquist-3 CPM scheme with coherent encoding. Such a scheme can be demodulated in substantially the same manner as signals modulated using M-PSK.
摘要翻译： CPM信号的相干调制方案。所公开的方案通过使用相干编码器避免了由差分编码引起的误差概率增加。可以通过使用具有相干编码的奈奎斯特-3 CPM方案来实现简单的解调器。这样的方案可以以与使用M-PSK调制的信号基本相同的方式进行解调。

104. 发明授权

US5311553A Trellis coding technique to increase adjacent channel interference protection ratio in land mobile radio systems under peak power constraints 失效
标题翻译：网格编码技术在峰值功率约束下增加陆地移动无线电系统中的相邻信道干扰保护比
公开(公告)号：US5311553A
公开(公告)日：1994-05-10
申请号：US975201
申请日：1992-06-15
申请人： Sandeep Chennakeshu , Rajaram Ramesh , Amer A. Hassan , John B. Anderson
发明人： Sandeep Chennakeshu , Rajaram Ramesh , Amer A. Hassan , John B. Anderson
IPC分类号： H04Q7/36 , H03M13/00 , H03M13/25 , H04L27/00 , H04L27/18 , H04L5/12
CPC分类号： H03M13/256 , H03M13/00 , H03M13/25 , H04L27/186
摘要： An optimum communication system employs an encoder coupled to a mapper and two parallel branches, each branch having a transmit filter a digital-to-analog converter, a low pass filter and a modulator coupled in series. Both modulators are coupled to a summer which provides an rf signal to a transmit antenna. A second antenna is coupled to a first down converter, an IF filter, a second down converter, an analog-to-digital converter and a decoder. The encoder is optimized by choosing a desired minimum Euclidean distance between symbols multiplied by the average to peak transmit power ratio (MPDR), an encoder alphabet and a number of constellation points. All possible encoder states and all possible input symbols are permutated to result in a plurality of encoder sets. The minimum distance between coded symbols and a P.sub.ib /P.sub.ab power ratio for each code set is determined. The encoder is adapted to output an encoder set U having a largest P.sub.ib /P.sub.ab power ratio having a large adjacent channel interference protection ratio. In an alternative embodiment, a minimum P.sub.ib /P.sub.ab power ratio (MPR) is chosen. The encoder is adapted to output an encoder set U having the largest minimum distance between coded symbols multiplied by the average to peak transmitted power ratio, that also has a P.sub.ib /P.sub.ab ratio that exceeds MPR.
摘要翻译：最佳通信系统采用耦合到映射器和两个并行分支的编码器，每个分支具有发射滤波器，数模转换器，低通滤波器和串联耦合的调制器。两个调制器耦合到向发射天线提供射频信号的夏季。第二天线耦合到第一下变换器，IF滤波器，第二下变频器，模数转换器和解码器。通过选择符号乘以平均与峰值发射功率比（MPDR），编码器字母和星座点数之间的期望的最小欧几里德距离来优化编码器。所有可能的编码器状态和所有可能的输入符号被排列以产生多个编码器组。确定每个代码集的编码符号与Pib / Pab功率比之间的最小距离。编码器适于输出具有大的相邻信道干扰保护比的具有最大Pib / Pab功率比的编码器组U。在替代实施例中，选择最小Pib / Pab功率比（MPR）。编码器适于输出编码符号之间具有最大最小距离乘以平均值与峰值发射功率比的编码器组U，其也具有超过MPR的Pib / Pab比。

105. 发明授权

US08754280B2 Method for start-up of an oxygenate-to-olefin process 失效
标题翻译：启动含氧化合物至烯烃工艺的方法
公开(公告)号：US08754280B2
公开(公告)日：2014-06-17
申请号：US13606308
申请日：2012-09-07
申请人： Leslie Andrew Chewter , Rajaram Ramesh , Sivakumar Sadasivan Vijayakumari , Jeroen Van Westrenen
发明人： Leslie Andrew Chewter , Rajaram Ramesh , Sivakumar Sadasivan Vijayakumari , Jeroen Van Westrenen
IPC分类号： C07C1/20
CPC分类号： C07C1/22 , C07C1/20 , C07C29/48 , C07C41/06 , C07C2529/40 , C07C2529/70 , C07D301/03 , Y02P30/42 , C07C11/06 , C07C11/04 , C07C43/046
摘要： The present invention provides a method for start-up of an Oxygenate-to-Olefins process, which process comprises the steps: a) providing an oxygenate-comprising feedstock to an Oxygenate-to-Olefins reaction zone and contacting the feedstock with a zeolite-comprising catalyst at a temperature in the range of from 450 to 700° C. ° C., to obtain an reaction product containing olefins; b) separating the reaction product obtained in step a) in at least a product fraction containing ethylene and/or propylene and a product fraction containing C4+ olefins; c) recycling at least part of the C4+ olefins in the product fraction containing C4+ olefins to the Oxygenate-to-Olefins reaction zone in step (a), characterized in that upon start-up the oxygenate-comprising feedstock initially comprises a first amount of externally supplied tert-alkyl ether and subsequently the amount of externally supplied tert-alkyl ether in the oxygenate-comprising feedstock is reduced.
摘要翻译：本发明提供了一种启动氧化烯 - 烯烃工艺的方法，该方法包括以下步骤：a）将含氧化合物的原料提供到氧化烯 - 烯烃反应区，并使原料与沸石 - 在450-700℃的温度范围内包含催化剂，得到含有烯烃的反应产物; b）将至少含有乙烯和/或丙烯的产物级分和含有C4 +烯烃的产物级分的步骤a）中获得的反应产物分离; c）在步骤（a）中将至少部分含有C4 +烯烃的产物级分中的C4 +烯烃再循环到步骤（a）中的氧化烯 - 烯烃反应区，其特征在于，在启动时，含氧化合物原料最初包含第一量外部供应的叔烷基醚，随后在含氧化合物的原料中外部供应的叔烷基醚的量减少。

106. 发明授权

US08704027B2 Process for preparing ethylene and propylene 失效
标题翻译：制备乙烯和丙烯的方法
公开(公告)号：US08704027B2
公开(公告)日：2014-04-22
申请号：US13606189
申请日：2012-09-07
申请人： Leslie Andrew Chewter , Rajaram Ramesh , Jeroen Van Westrenen
发明人： Leslie Andrew Chewter , Rajaram Ramesh , Jeroen Van Westrenen
IPC分类号： C07C2/00
CPC分类号： C07C1/22 , C07C1/20 , C07C4/06 , C07C29/48 , C07C2529/42 , C07C2529/70 , C07C2529/83 , C07C2529/85 , C07D301/03 , Y02P30/42 , C07C11/04 , C07C11/06
摘要： The present invention provides a process for preparing ethylene and/or propylene, comprising the steps of contacting a stream comprising C4+ olefins with a zeolite-comprising catalyst to retrieve an olefinic product stream comprising ethylene and/or propylene, and a C4+ hydrocarbon fraction, comprising paraffins, normal olefins and iso-olefins. The C4+ hydrocarbon fraction is subjected to an etherification process with wherein at least part of the iso-olefins are converted with methanol and/or ethanol to an tert-alkyl ether and an etherification product stream is retrieved and separated into an ether-enriched stream and an iso-olefin-depleted C4+ hydrocarbon stream. Part of the iso-olefin-depleted C4+ hydrocarbon stream from the process to purge part of the paraffinic C4+ hydrocarbons while another part of the iso-olefin-depleted C4+ hydrocarbon stream is recycled. The tert-alkyl ether in the ether-enriched stream is converted to ethylene and/or propylene by contacting at least part of the ether-enriched stream with a molecular sieve-comprising catalyst.
摘要翻译：本发明提供一种制备乙烯和/或丙烯的方法，包括以下步骤：使包含C4 +烯烃的料流与含沸石的催化剂接触以回收包含乙烯和/或丙烯的烯烃产物流和C4 +烃馏分，其包含石蜡，正烯烃和异烯烃。对C4 +烃馏分进行醚化处理，其中至少部分异烯烃用甲醇和/或乙醇转化成叔烷基醚，并将醚化产物流回收并分离成富醚流，一种异烯烃贫化的C4 +烃流。来自该方法的部分烯烃贫化的C4 +烃流，以清除部分链烷烃C4 +烃，而另一部分异烯烃贫化的C4 +烃流被回收。通过使至少部分富含乙醚的料流与含分子筛的催化剂接触，使富醚流中的叔烷基醚转化为乙烯和/或丙烯。

107. 发明授权

US07885619B2 Diversity transmission using a single power amplifier 有权
标题翻译：使用单个功率放大器进行分集传输
公开(公告)号：US07885619B2
公开(公告)日：2011-02-08
申请号：US11808769
申请日：2007-06-12
申请人： Jung-Fu Cheng , Leonid Krasny , Rajaram Ramesh
发明人： Jung-Fu Cheng , Leonid Krasny , Rajaram Ramesh
IPC分类号： H04B7/02 , H01Q11/12
CPC分类号： H04B7/0682 , H04B7/0404 , H04B7/0634
摘要： Diversity radio transmission is accomplished with excellent performance using multiple antennas receiving a transmission signal from a single power amplifier. A data signal to be transmitted is provided to a first antenna, and a phase-shifted version of the data signal is applied a second antenna. The relative phase shift between the data signal transmitted over the two transmit antennas ensures the two antenna signals can be constructively combined at the receiver. In one non-limiting example embodiment, the relative phase shift is determined by processing pilot signals sent along with the data signal and which are transmitted with predetermined phase shifts.
摘要翻译：使用接收来自单个功率放大器的传输信号的多个天线，以卓越的性能来实现分集无线电传输。要发送的数据信号被提供给第一天线，并且数据信号的相移版本被应用于第二天线。通过两个发射天线发射的数据信号之间的相对相移确保了两个天线信号可以在接收机上被建设性地组合。在一个非限制性示例实施例中，相对相移通过处理与数据信号一起发送并且以预定相移发送的导频信号来确定。

108. 发明授权

US07321646B2 Methods and apparatus for pre-filtering a signal to increase signal-to-noise ratio and decorrelate noise 有权
标题翻译：用于对信号进行预滤波以提高信噪比并去噪声的方法和装置
公开(公告)号：US07321646B2
公开(公告)日：2008-01-22
申请号：US10716085
申请日：2003-11-18
申请人： Huseyin Arslan , Abdulrauf Hafeez , Rajaram Ramesh , Dennis Hui
发明人： Huseyin Arslan , Abdulrauf Hafeez , Rajaram Ramesh , Dennis Hui
IPC分类号： H04B1/10
CPC分类号： H04L25/03133 , H04L2025/03605
摘要： To receive a signal from a multiple-input-multiple-output (MIMO) communication channel, initial channel taps are generated based on an impulse response estimate of the MIMO communication channel. The received signal is pre-filtered using the initial channel taps to generate output channel taps and a corresponding output signal having an increased signal-to-noise ratio (SNR) and uncorrelated noise. The SNR is based on a ratio of the energy in a first subset of the output channel taps to the energy in a second subset of the output channel taps.
摘要翻译：为了从多输入多输出（MIMO）通信信道接收信号，基于MIMO通信信道的脉冲响应估计来生成初始信道抽头。使用初始信道抽头对接收到的信号进行预滤波以产生输出信道抽头和具有增加的信噪比（SNR）和不相关噪声的相应输出信号。 SNR基于输出信道抽头的第一子集中的能量与输出信道抽头的第二子集中的能量的比率。

109. 发明申请

US20060067383A1 Parameter estimate initialization using interpolation 审中-公开
公开(公告)号：US20060067383A1
公开(公告)日：2006-03-30
申请号：US10953010
申请日：2004-09-29
申请人： Carmela Cozzo , Gregory Bottomley , Rajaram Ramesh
发明人： Carmela Cozzo , Gregory Bottomley , Rajaram Ramesh
IPC分类号： H04B1/707 , H04B1/69
CPC分类号： H04B1/712 , H04B1/7117 , H04B2201/709727
摘要： A receiver is described herein that is capable of receiving and processing a radio signal and further capable of using interpolation to initialize receiver parameters when there is a change in at least one delay associated with the received radio signal or when there is at least one new correlator position. For instance, the receiver parameters that can be initialized include: (1) channel coefficients; (2) AFC parameters; (3) tracking parameters; (4) noise statistics (noise correlations); (5) signal statistics (channel coefficient correlations); (6) data statistics (despread values or chip samples); or (7) combining weights.

110. 发明授权

US06853633B1 Methods of providing signal parameter information using delta-modulation and related systems and terminals 有权
标题翻译：使用增量调制和相关系统和终端提供信号参数信息的方法
公开(公告)号：US06853633B1
公开(公告)日：2005-02-08
申请号：US09669361
申请日：2000-09-26
申请人： Rajaram Ramesh
发明人： Rajaram Ramesh
IPC分类号： H04B7/005 , H04B14/06 , H04B7/212 , H04J3/00 , H04Q11/04 , H04J3/314
CPC分类号： H04W52/228 , H04B14/064 , H04W52/225 , H04W52/241 , H04W52/247
摘要： Signal parameter information can be transmitted from a first communications device to a second communications device. For example, communications can be received at the first communications device from the second communications device, and a plurality of samples of a signal parameter can be generated characterizing the received communications. In addition, a plurality of delta-modulation values can be calculated responsive to the respective samples of the signal parameter wherein the plurality of delta-modulation values are associated with corresponding ones of the plurality of samples of the signal parameter characterizing the received communications. The delta-modulation values can be transmitted to the second communications device. Related devices are also discussed.
摘要翻译：信号参数信息可以从第一通信设备发送到第二通信设备。例如，可以从第二通信设备在第一通信设备处接收通信，并且可以生成表征所接收的通信的信号参数的多个样本。此外，可以响应于信号参数的相应样本来计算多个Δ调制值，其中多个Δ调制值与表征接收到的通信的信号参数的多个样本中的相应样本相关联。 Δ调制值可以被发送到第二通信设备。还讨论了相关设备。

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