公开(公告)号：US07012883B2

公开(公告)日：2006-03-14

申请号：US09991039

申请日：2001-11-21

Applicant: Ahmad Jalali ,  Ivan Jesus Fernandez Corbaton

Inventor： Ahmad Jalali ,  Ivan Jesus Fernandez Corbaton

IPC: H04J11/00

CPC classification number: H04L5/006 ,  H04L1/0002 ,  H04L1/0021 ,  H04L1/0023 ,  H04L1/1819 ,  H04L5/0007 ,  H04L5/0046 ,  Y02D50/10

Abstract: Techniques to determine the rate for a data transmission in an OFDM system. The maximum data rate that may be reliably transmitted over a given multipath (non-flat) channel by the OFDM system is determined based on a metric for an equivalent (flat) channel. For the given multipath channel and a particular rate (which may be indicative of a particular data rate, modulation scheme, and coding rate), the metric is initially derived from an equivalent data rate and the particular modulation scheme. A threshold SNR needed to reliably transmit the particular data rate using the particular modulation scheme and coding rate is then determined. The particular rate is deemed as being supported by the multipath channel if the metric is greater than or equal to the threshold SNR. Incremental transmission is used to account for errors in the determined data rate.

公开(公告)号：US06888805B2

公开(公告)日：2005-05-03

申请号：US09816558

申请日：2001-03-23

Applicant: Paul Bender ,  Ahmad Jalali ,  Bruce Judson ,  Roberto Padovani ,  Charles E. Wheatley, III

Inventor： Paul Bender ,  Ahmad Jalali ,  Bruce Judson ,  Roberto Padovani ,  Charles E. Wheatley, III

IPC: H04B7/26 ,  H04J3/00 ,  H04W16/02 ,  H04W16/12 ,  H04Q7/00 ,  H04B7/216 ,  H04Q7/20

CPC classification number: H04W16/12 ,  H04B7/2618 ,  H04W16/02

Abstract: A “time multiplexed” transmission scheme capable of reducing the amount of interference from other cells operated at the same frequency band. Each cell in a system transmits in designated time intervals (e.g., time slots) during which other interfering cells may be prevented from transmitting. By temporarily “blanking” transmissions from interfering cells during the designated time slots, the amount of interference from these cells is reduced. The improved signal quality may support transmission at a desired or higher data rate, which may not be possible without cell blanking. In one variant, transmissions from the cells are staggered over different time slots. A set of one or more cells may be designated to transmit in each of a number of slot phases. The cells transmit in a staggered manner on these phases to reduce interference. The transmission scheme may be used for a various channel types (e.g., a control channel) and applications.

Abstract translation: “时分复用”传输方案能够减少在相同频带上工作的其他小区的干扰量。 系统中的每个小区以指定的时间间隔（例如，时隙）发送，在该时间间隔期间可以防止其他干扰小区的发射。 通过在指定时隙期间暂时从干扰小区“消隐”传输，减少了来自这些小区的干扰量。 改进的信号质量可以支持以期望的或更高数据速率的传输，这在没有小区消隐的情况下可能是不可能的。 在一个变型中，来自小区的传输在不同的时隙上交错。 可以指定一组一个或多个小区在多个时隙相位中的每一个中进行发送。 小区在这些相位上以交错的方式发送以减少干扰。 传输方案可以用于各种信道类型（例如，控制信道）和应用。

公开(公告)号：US06778507B1

公开(公告)日：2004-08-17

申请号：US09388267

申请日：1999-09-01

Applicant: Ahmad Jalali

Inventor： Ahmad Jalali

IPC: H04B700

CPC classification number: H04B7/0617 ,  H04B7/0632

Abstract: In a CDMA data communication system capable of variable rate transmission, utilization of beamforming techniques decreases the average interference caused by transmissions of a base station to subscriber stations in neighboring cells. Base stations utilize multiple transmit antennas, each transmitting signals at controlled phases, to form transmit signal beams corresponding to individual subscriber stations. Data and reference signals are transmitted along beams that change according to fixed time slots and sub-slots in order to maximize carrier-to-interference ratios (C/I) measured at subscriber stations.

Abstract translation: 在能够进行可变速率传输的CDMA数据通信系统中，波束成形技术的利用减少了基站对相邻小区中的用户站的传输所造成的平均干扰。 基站利用多个发射天线，每个发射天线以受控的相位传输信号，以形成对应于各个用户台的发射信号波束。 数据和参考信号沿着根据固定时隙和子时隙而变化的波束发送，以便最大化在用户台测量的载波干扰比（C / I）。

公开(公告)号：US06751206B1

公开(公告)日：2004-06-15

申请号：US09608173

申请日：2000-06-29

Applicant: Roberto Padovani ,  Paul E. Bender ,  Ahmad Jalali ,  Bruce Judson ,  Charles E. Wheatley, III

Inventor： Roberto Padovani ,  Paul E. Bender ,  Ahmad Jalali ,  Bruce Judson ,  Charles E. Wheatley, III

IPC: H04B7204

CPC classification number: H04W16/12 ,  H04W16/02

Abstract: In a CDMA data communication system capable of variable rate transmission, utilization of beam switching techniques decreases the average interference caused by transmissions of a base station to subscriber stations within a cell, and in neighboring cells. Base stations utilize multiple transmit antennas, each transmitting signals at controlled amplitudes and phases, to form transmit signal corresponding to sector divisions. Data and reference signals are transmitted along sector division beams that alternate according to fixed time slots in order to increase system capacity and data rates by maximizing carrier-to-interference ratios (C/I) measured at subscriber stations.

Abstract translation: 在能够进行可变速率传输的CDMA数据通信系统中，波束切换技术的利用减少了由基站向小区内和相邻小区中的用户台的传输引起的平均干扰。 基站利用多个发射天线，每个发射天线以受控的幅度和相位传输信号，以形成对应于扇区划分的发射信号。 数据和参考信号沿着根据固定时隙交替的扇区分波束传输，以通过最大化在用户台测量的载波干扰比（C / I）来增加系统容量和数据速率。

公开(公告)号：US06373831B1

公开(公告)日：2002-04-16

申请号：US09047604

申请日：1998-03-25

Applicant: Norman P. Secord ,  Mo-Han Fong ,  Geng Wu ,  Leo Strawczynski ,  Ahmad Jalali ,  Robert Matyas ,  Ning Guo ,  Wookwon Lee ,  Amir Bigloo

Inventor： Norman P. Secord ,  Mo-Han Fong ,  Geng Wu ,  Leo Strawczynski ,  Ahmad Jalali ,  Robert Matyas ,  Ning Guo ,  Wookwon Lee ,  Amir Bigloo

IPC: H04B7216

CPC classification number: H04L1/0066 ,  H04L1/0041 ,  H04L1/0071 ,  H04L5/026

Abstract: Methods and apparatus for transmitting data over a multi-channel CDMA system are disclosed in accordance with the teachings of the present invention wherein the system includes an encoder for encoding a data stream with error correction, an interleaver for interleaving the data stream, a multiplexor for multiplexing a plurality of power control symbols onto the data stream, and an inverse-multiplexor for inverse-multiplexing the data stream onto multiple different communication channels. The system may also include additional error correction encoding and interleaving steps.

Abstract translation: 根据本发明的教导公开了用于通过多信道CDMA系统发送数据的方法和装置，其中系统包括用于对具有纠错的数据流进行编码的编码器，用于交织数据流的交织器，用于对数据流进行交织的多路复用器 将多个功率控制符号复用到数据流上，以及用于将数据流逆向多路复用到多个不同通信信道上的反相多路复用器。 该系统还可以包括附加的纠错编码和交错步骤。

公开(公告)号：US06233455B1

公开(公告)日：2001-05-15

申请号：US09304144

申请日：1999-05-03

Applicant: Deepa Ramakrishna ,  Ahmad Jalali ,  Ashvin Chheda

Inventor： Deepa Ramakrishna ,  Ahmad Jalali ,  Ashvin Chheda

IPC: H04Q720

CPC classification number: H04W36/18

Abstract: A pre-determined negative constant is utilized in soft handoff mode to permit a new pilot signal to be added to an wireless phone's active set. The negative constant is combined with the weakest pilot signal in the active set and then compared to the new pilot signal strength which allows the new pilot to trigger a Pilot Strength Measurement Message (PSMM) even when the new pilot signal is weaker than all active set pilot signals. The negative constant provides a soft handoff while maintaining or reducing drop rate probabilities and frame error rates. After initially triggering a PSMM, the next instance the new pilot may ordinarily cause a PSMM to be triggered is when the new pilot signal exceeds the strongest active set pilot signal. Triggering a PSMM when exceeding the strongest active set signal may increase the probability of dropped signals. To reduce the probability of dropped signals, a negative constant is utilized during soft handoff to add a new pilot to an active set. This step would also decrease the probability that the new pilot will overpower a weaker active set pilot signal.

Abstract translation: 在软切换模式中使用预定的负常数以允许将新的导频信号添加到无线电话的活动集。 负的常数与有源集中的最弱的导频信号相组合，然后与新的导频信号强度进行比较，即使新的导频信号弱于所有的有效集合，允许新导频触发导频强度测量消息（PSMM） 导频信号。 负常数提供软切换，同时保持或降低丢弃率概率和帧错误率。 在最初触发PSMM之后，新的导频通常可以引起PSMM被触发的下一个例子是当新的导频信号超过最强的有效集导频信号时。 超过最强有效设定信号时触发PSMM可能会增加掉线信号的概率。 为了降低丢弃信号的概率，在软切换期间利用负常数将新的导频添加到活动集。 这一步骤也将降低新的飞行员将会超过较弱的主动集合导频信号的可能性。

公开(公告)号：US6160999A

公开(公告)日：2000-12-12

申请号：US937305

申请日：1997-08-18

Applicant: Ashvin H. Chheda ,  Ahmad Jalali

Inventor： Ashvin H. Chheda ,  Ahmad Jalali

IPC: H04B7/005 ,  H04W36/18 ,  H04W52/40 ,  H04B1/00

CPC classification number: H04W52/40 ,  H04W36/18

Abstract: A wireless communication system facilitates wireless communication with a mobile unit operating within a respective service area. The wireless communication system includes a mobile switching center and a plurality of base stations with each base stations coupled to the mobile switching center and providing wireless coverage within a respective portion of the service area. The mobile unit wirelessly connects to at least two of the base stations (or sectors of the base stations) that transmit to the mobile unit via respective forward links at respective transmit levels. These respective transmit levels are based upon forward link requirements of the mobile unit. The mobile unit transmits to the at least two base stations/sectors via a respective plurality of reverse links. Forward link transmit levels may be determined based upon the quality of corresponding reverse link transmissions or from the quality of pilot signals or forward link transmissions received by the mobile unit. Forward link transmissions are made via the most favorable forward links (at least one) while transmissions are not made, or are made at reduced power levels on the least favorable forward links. During management of the wireless communication system, forward link transmissions are initiated and discontinued based upon the forward link transmission power requirements of the mobile unit. While managing the forward link transmissions, the forward link transmission power requirements of the mobile unit may be compared to a plurality of thresholds. When these thresholds are exceeded, the management requires altering which base stations make forward link transmissions and at what levels such transmissions are made. In a particular embodiment of the wireless communication system, the system operates according to a code division multiple access protocol.

Abstract translation: 无线通信系统促进与在相应服务区域内操作的移动单元的无线通信。 无线通信系统包括移动交换中心和多个基站，每个基站耦合到移动交换中心，并在服务区域的相应部分内提供无线覆盖。 移动单元通过相应的发送电平的各自的前向链路与至少两个基站（或基站的扇区）无线地连接。 这些各自的传输级别基于移动单元的前向链路要求。 移动单元经由相应的多个反向链路向至少两个基站/扇区发送。 可以基于对应的反向链路传输的质量或由移动单元接收的导频信号或前向链路传输的质量来确定前向链路传输级别。 通过最不利的前向链路（至少一个）进行前向链路传输，而不进行传输，或者在最不利的前向链路上以较低的功率级别进行传输。 在无线通信系统的管理期间，基于移动单元的前向链路发送功率需求，发起和中断前向链路传输。 在管理前向链路传输时，可以将移动单元的前向链路传输功率要求与多个阈值进行比较。 当超过这些阈值时，管理需要改变哪些基站进行前向链路传输，并且在什么级别进行这样的传输。 在无线通信系统的特定实施例中，系统根据码分多址协议进行操作。

公开(公告)号：US6075815A

公开(公告)日：2000-06-13

申请号：US931991

申请日：1997-09-17

Applicant: Ashvin Chheda ,  Michael S. Feeney ,  Ahmad Jalali

Inventor： Ashvin Chheda ,  Michael S. Feeney ,  Ahmad Jalali

IPC: H04B7/005 ,  H04B17/00

CPC classification number: H04W52/24 ,  H04W52/12 ,  H04W52/20 ,  H04W52/225 ,  H04W52/40

Abstract: The process determines the I channel and Q channel components for each received soft value. The location of each soft value with respect to the fade line is determined using the I and Q channel components. These locations are averaged over a power control group duration to determine the noise density. The symbol energy is determined by subtracting the average perpendicular distance from the soft value point to the fade line from half the square of the average of the distance from the soft value point to the origin.

Abstract translation: 该过程确定每个接收的软值的I通道和Q通道组件。 使用I和Q通道分量来确定每个软值相对于淡入淡出线的位置。 这些位置在功率控制组持续时间内被平均以确定噪声密度。 通过从软值点到从原始值的距离的平均值的平方的平方的一半减去从软值点到褪色线的平均垂直距离来确定符号能量。

公开(公告)号：US6073025A

公开(公告)日：2000-06-06

申请号：US932253

申请日：1997-09-17

Applicant: Ashvin Chheda ,  Michael S. Feeney ,  Ahmad Jalali

Inventor： Ashvin Chheda ,  Michael S. Feeney ,  Ahmad Jalali

IPC: H04B7/005 ,  H04B1/06 ,  G01F3/02 ,  H04Q7/00

CPC classification number: H04W52/283 ,  H04W52/282 ,  H04W52/40 ,  H04W52/08

Abstract: The base station controller monitors the reverse link frame error rate of all the base stations involved in a soft hand-off with a radiotelephone. The average reverse link frame error rates of these base stations are then computed and the lowest of the average error rates is found. The last known transmit power of the base station having the lowest average error rate is determined. The transmit power of those base stations having a higher average reverse link frame error rate than the best base station are adjusted to the last known transmit power of the best base station.

Abstract translation: 基站控制器用无线电话机监视与软切换有关的所有基站的反向链路帧错误率。 然后计算这些基站的平均反向链路帧错误率，并且找到平均错误率的最低值。 确定具有最低平均误码率的基站的最后已知发射功率。 具有比最佳基站更高的平均反向链路帧错误率的那些基站的发射功率被调整到最佳基站的最后已知的发射功率。

公开(公告)号：US6038448A

公开(公告)日：2000-03-14

申请号：US899105

申请日：1997-07-23

Applicant: Ashvin H. Chheda ,  Ahmad Jalali

Inventor： Ashvin H. Chheda ,  Ahmad Jalali

IPC: H04W16/24 ,  H04W36/30 ,  H04B7/20

CPC classification number: H04W36/30 ,  H04W16/24

Abstract: A wireless communication system facilitates wireless communication with a mobile unit within a respective service area. The wireless communication system includes a mobile switching center and a plurality of base stations. Each base station couples to the mobile switching center and provides wireless communication within a respective cell or within a plurality of respective sectors. Each base station provides a pilot signal that may be received by the wireless mobile unit. With multiple sectors, a pilot signal is provided for each sector. The mobile unit may wirelessly connect to any of the base stations' cells and sectors. A determination of whether to be connected to a particular base station cell and/or base station sector is based upon the relative strengths of pilot signals received by the wireless mobile unit. The mobile unit may evaluate the relative strengths of received pilot signals and simply request a connection to a base station or a disconnection therefrom based upon the evaluation. However, the mobile unit may also notify the mobile switching center of strengths of received pilot signals with the mobile switching center taking action. In such case, the mobile switching center may determine thresholds and pass the thresholds to the mobile unit for later use, the thresholds based upon the relative strengths of the pilot signals. A corresponding method includes steps for operating a wireless communication system.

Abstract translation: 无线通信系统促进与相应服务区域内的移动单元的无线通信。 无线通信系统包括移动交换中心和多个基站。 每个基站耦合到移动交换中心，并在相应小区内或多个相应扇区内提供无线通信。 每个基站提供可由无线移动单元接收的导频信号。 对于多个扇区，为每个扇区提供导频信号。 移动单元可以无线地连接到任何基站的小区和扇区。 是否连接到特定基站小区和/或基站扇区的确定是基于由无线移动单元接收的导频信号的相对强度。 移动单元可以评估所接收的导频信号的相对强度，并且基于该评估简单地请求到基站的连接或其断开连接。 然而，移动单元还可以通过移动交换中心采取行动来通知移动交换中心接收到的导频信号的强度。 在这种情况下，移动交换中心可以确定阈值并将阈值传递给移动单元供以后使用，该阈值基于导频信号的相对强度。 相应的方法包括用于操作无线通信系统的步骤。