公开(公告)号：US20020159395A1

公开(公告)日：2002-10-31

申请号：US09792637

申请日：2001-02-23

Applicant: Tantivy Communications, Inc.

Inventor： George Rodney Nelson JR. ,  James A. Proctor JR. ,  John E. Hoffmann ,  Antoine J. Rouphael

IPC: H04L012/26

CPC classification number: H04W72/042 ,  H04J13/00 ,  H04J13/0003 ,  H04L5/22 ,  H04W24/00 ,  H04W28/22 ,  H04W48/08 ,  H04W52/24 ,  H04W52/26 ,  H04W52/365 ,  H04W72/0406 ,  H04W72/0446 ,  H04W72/0466 ,  H04W72/0473 ,  H04W72/048 ,  H04W72/1289 ,  Y02D70/00

Abstract: Data rate allocation decisions are made for a communications channel, such as a wireless reverse link connection. A first parameter used in this determination is a path loss, which is determined by the following process. First, a message is sent from a first station to a second station, such as on a paging channel. The message indicates a forward Effective Radiated Power (ERP) of a pilot signal transmitted by the first station. The second station then determines the received signal strength of this pilot signal, taking into account receiver gains. The path loss can then be estimated by the second station as the difference between the forward ERP data value that it received and the detected received pilot power. The second station also then preferably determines a transmit power level when transmitting a message back to the first station. This transmit power level information is encoded as a digital data word together with the forward path loss information as calculated by the first station. Upon receipt of these two pieces of information by the first station, the forward path loss estimate as calculated by the second station, and the output power value of the second station, the first station can then determine the amount of excess power available at the field unit. This excess power difference is indicative of the amount of dynamic range available in the transmit power amplifier in the particular second station. With this information, the first station can then make a determination as to whether coding rates which require a higher dynamic range will be acceptable for use by the particular second station.

Abstract translation: 对于诸如无线反向链路连接的通信信道进行数据速率分配决定。 在该确定中使用的第一参数是通过以下过程确定的路径损耗。 首先，消息从第一站发送到第二站，例如在寻呼信道上。 该消息指示由第一站发送的导频信号的前向有效辐射功率（ERP）。 然后，第二站根据接收机增益确定该导频信号的接收信号强度。 然后可以由第二站估计路径损耗作为其接收到的前向ERP数据值与检测到的接收导频功率之间的差值。 然后，当发送消息回到第一站时，第二站优选地确定发射功率电平。 该发送功率电平信息与由第一电台计算出的正向路径损耗信息一起被编码为数字数据字。 在由第一站接收到这两条信息时，由第二站计算出的正向路径损耗估计值和第二站的输出功率值，则第一站然后可以确定在现场可用的多余的功率量 单元。 该过剩功率差表示特定第二站中的发射功率放大器中可用的动态范围的量。 利用该信息，第一站然后可以确定需要更高动态范围的编码率是否可被特定的第二站使用。

公开(公告)号：US20020080024A1

公开(公告)日：2002-06-27

申请号：US09775305

申请日：2001-02-01

Applicant: Tantivy Communications, Inc.

Inventor： G. Rodney Nelson JR. ,  John E. Hoffmann ,  Antoine J. Rouphael ,  James A. Proctor JR.

IPC: H04B007/01

CPC classification number: H04W56/0085 ,  H04B7/2637

Abstract: Multiple field units in a CDMA system are synchronized for communication with a base station using shared forward and reverse link channels. In an illustrative embodiment, each field unit is assigned a time slot in a forward link channel to receive messages from the base station. Likewise, each field unit is assigned a time slot on a common reverse link channel for transmitting messages to the base station. Timing alignment and power level control among each of many field units and the base station is achieved by analyzing messages received at the base station in a corresponding time slot as transmitted by each field unit. Thereafter, a message is transmitted from the base station in a corresponding time slot to a particular field unit for adjusting its timing or power level so that future messages transmitted from the field unit are received in the appropriate time slot at the base station at a desired power level. In this way, minimal resources are deployed to maintain communication and precise synchronization between a base station and each of multiple users, minimizing collisions between field units transmitting in adjacent time slots on the reverse link. This method reduces the frequency a field unit must rely on the use of a slotted aloha random access channel according to IS-95.

Abstract translation: CDMA系统中的多个场单元被同步，以使用共享的前向和反向链路信道与基站进行通信。 在说明性实施例中，每个现场单元在前向链路信道中分配时隙以从基站接收消息。 类似地，每个现场单元在公共反向链路信道上分配一个时隙，用于向基站发送消息。 通过在每个场单元发送的相应时隙中分析在基站处接收的消息来实现许多场单元和基站中的每一个中的定时对准和功率电平控制。 此后，在对应的时隙中从基站发送消息到特定的现场单元，以调整其定时或功率电平，使得在现场单元发送的未来消息在基站的适当时隙中以期望的 能量等级。 以这种方式，部署最小资源以维持基站与多个用户中的每一个之间的通信和精确同步，从而最小化在反向链路上的相邻时隙中发送的现场单元之间的冲突。 该方法降低了场单元必须依赖于使用根据IS-95的时隙aloha随机接入信道的频率。

公开(公告)号：US20010048709A1

公开(公告)日：2001-12-06

申请号：US09773253

申请日：2001-01-31

Applicant: Tantivy Communications, Inc.

Inventor： John E. Hoffmann ,  George Rodney Nelson JR. ,  Daniel I. Riley ,  Antoine J. Rouphael ,  James A. Proctor JR.

IPC: H04B001/69

CPC classification number: H04L1/0048 ,  G11B20/1833 ,  H03M13/35 ,  H04B1/707 ,  H04J13/00 ,  H04L1/0003 ,  H04L1/0007 ,  H04L1/0009 ,  H04L1/0025 ,  H04L1/1809 ,  H04L1/1816 ,  H04L25/14 ,  H04L27/22 ,  H04L27/38 ,  H04L2001/0093 ,  H04L2001/0096

Abstract: The present invention provides for making code rate adjustments and modulation type adjustments in a pseudonoise (PN) encoded CDMA system. Coding rate adjustments may be made by changing the number of information bits per symbol, or Forward Error Code (FEC) coding rate. A forward error correction (FEC) block size is maintained at a constant amount. Therefore, as the number of information bits per symbol are increased, an integer multiple of bits per epoch is always maintained. The scheme permits for a greater flexibility and selection of effective data rates providing information bit rates ranging from, for example, approximately 50 kilobits per second to over 5 mega bits per second (Mbps) in one preferred embodiment.

Abstract translation: 本发明提供了在伪噪声（PN）编码的CDMA系统中进行码率调整和调制类型调整。 可以通过改变每个符号的信息比特数或转发错误码（FEC）编码率来进行编码速率调整。 前向纠错（FEC）块大小保持恒定的量。 因此，随着每个符号的信息位的数量增加，始终保持每个时期的位的整数倍。 在一个优选实施例中，该方案允许更大的灵活性和有效数据速率的选择，从而提供从例如大约50千比特每秒到超过5兆比特每秒（Mbps）的信息比特率。

公开(公告)号：US20010033579A1

公开(公告)日：2001-10-25

申请号：US09792410

申请日：2001-02-23

Applicant: Tantivy Communications, Inc.

Inventor： George R. Nelson JR. ,  James A. Proctor JR. ,  John E. Hoffmann ,  Antoine J. Rouphael

IPC: H04L012/413

CPC classification number: H04W52/242 ,  H04L1/1607 ,  H04L12/5602 ,  H04L47/14 ,  H04L47/26 ,  H04L2001/0093 ,  H04W24/00 ,  H04W52/228 ,  H04W52/48 ,  H04W52/50 ,  H04W74/0825 ,  H04W74/0858

Abstract: In an illustrative embodiment of the present invention, a first channel is allocated for transmitting sporadically generated messages from multiple field units to a base station. The first channel is preferably divided into time slots in which a field unit transmits an access request message to the base station for establishing a communication link. In response to an access request message, feedback information is provided from the base station to multiple field units indicating whether a collision was detected on the first channel for a message transmitted in a previous time slot. In an instance when a collision is detected, the field unit will re-transmit an access request message at a previous power level setting based on a random back off time. If no collision is detected and the base station fails to transmit an acknowledgment message from the base station to the access requesting field unit, the power output level of the field unit is increased for successive message transmissions until the message is received.

Abstract translation: 在本发明的说明性实施例中，分配第一信道用于将来自多个场单元的偶发生成的消息发送到基站。 第一信道优选地被划分为时隙，其中，场单元向基站发送接入请求消息以建立通信链路。 响应于访问请求消息，反馈信息从基站提供给多个字段单元，指示在第一信道上是否检测到在先前时隙中发送的消息的冲突。 在检测到冲突的情况下，场单元将基于随机退避时间在先前功率电平设置下重新发送接入请求消息。 如果没有检测到冲突，并且基站无法从基站向接入请求字段单元发送确认消息，则对于连续的消息传输增加了现场单元的功率输出电平，直到接收到消息。