公开(公告)号：US5903862A

公开(公告)日：1999-05-11

申请号：US575287

申请日：1996-01-11

申请人： Lindsay A. Weaver, Jr. ,  S. Katherine Lam ,  William R. Gardner ,  Paul E. Jacobs ,  Andrew P. DeJaco ,  Gilbert C. Sih

发明人： Lindsay A. Weaver, Jr. ,  S. Katherine Lam ,  William R. Gardner ,  Paul E. Jacobs ,  Andrew P. DeJaco ,  Gilbert C. Sih

IPC分类号： G10L11/02 ,  G10L19/00 ,  G10L19/14 ,  H04B7/26 ,  H04B14/04 ,  H04Q11/04 ,  H04W88/18 ,  G10L9/18 ,  H04Q7/24

CPC分类号： H04W88/181 ,  G10L19/16

摘要： When one vocoding system is coupled to another vocoding system, a tandem arrangement results. The tandem configuration results in voice quality degradation as speech is encoded and decoded, then encoded and decoded again. One reason for the degradation is that postfiltering performed at the output of the speech decoding process introduces distortions in the spectral content of the reconstructed speech as compared to the original speech. The present invention prevents the degradation due to the use of postfilters by modifying the postfiltering within the vocoders where a tandem configuration exists. A detection code is embedded within the data signal to indicate the existence of a tandem configuration. If the detection code is received at a vocoder, modified vocoding is established within the vocoders to prevent the degradation due to the postfiltering.

摘要翻译： 当一个声码系统耦合到另一个声码系统时，会产生串联排列。 串音配置导致语音质量下降，因为语音被编码和解码，然后被再次编码和解码。 降级的一个原因是在语音解码过程的输出处执行的后置滤波与原始语音相比引入了重构语音的频谱内容中的失真。 本发明通过修改存在串列配置的声码器中的后置滤波来防止由于使用后置滤波器导致的劣化。 检测码嵌入在数据信号中以指示串联配置的存在。 如果在声码器处接收到检测码，则在声码器内建立修改后的声码，以防止由于后置滤波引起的劣化。

公开(公告)号：US5956673A

公开(公告)日：1999-09-21

申请号：US378300

申请日：1995-01-25

申请人： Lindsay A. Weaver, Jr. ,  S. Katherine Lam ,  William Gardner ,  Paul Jacobs

发明人： Lindsay A. Weaver, Jr. ,  S. Katherine Lam ,  William Gardner ,  Paul Jacobs

IPC分类号： G10L19/14 ,  H04W88/18 ,  G10L9/18 ,  H04Q7/24

CPC分类号： H04W88/181 ,  G10L19/16

摘要： A first remote vocoder receives analog voice and produces packetized vocoder data which is transmitted over a wireless link. A first local vocoder receives the packetized vocoder data from the wireless link. The first local vocoder converts the packetized data to a multibit PCM output. The first local vocoder also adds a detection code to one of the least significant bits (LSB) of the PCM output. The first local vocoder passes the PCM signal to the PSTN from the second end user. The first local vocoder also receives PCM input over the PSTN. The first local vocoder constantly monitors the least significant bit of the PCM input for a detection code indicating that a second local vocoder is connected at the receiving end. If the first local vocoder detects the detection code from the second local vocoder, it begins to substitute packetized data and a redundancy check for a second one of the LSB's of the outgoing PCM. The first local vocoder also begins to monitor the second one of the LSB's of the incoming PCM. If the redundancy check indicates that valid packetized data has been received, the first local vocoder stops converting the PCM output into packetized data and simply passes the packetized data on the second one of the LSB's to the first remote vocoder. If at any time the redundancy check fails and the detection code is not detected, the first local vocoder returns to converting the incoming PCM to packetized data. In this way, the tandem vocoding arrangement is avoided.

摘要翻译： 第一远程声码器接收模拟语音并产生通过无线链路发送的分组声码器数据。 第一本地声码器从无线链路接收分组声码器数据。 第一个本地声码器将打包数据转换成多位PCM输出。 第一本地声码器还将检测码添加到PCM输出的最低有效位（LSB）之一。 第一本地声码器从第二终端用户传递PCM信号到PSTN。 第一本地声码器也通过PSTN接收PCM输入。 第一本地声码器持续监视PCM输入的最低有效位，用于检测码，指示在接收端连接第二本地声码器。 如果第一本地声码器检测到来自第二本地声码器的检测码，则它开始替代分组数据和对出局PCM的LSB中的第二个的冗余校验。 第一个本地声码器也开始监视传入的PCM的第二个LSB。 如果冗余检查指示已经接收到有效的分组化数据，则第一本地语音编码器停止将PCM输出转换成分组化数据，并且将LSB的第二个上的分组数据简单地传递到第一远程声码器。 如果在任何时候冗余检查失败并且未检测到检测码，则第一本地声码器返回将输入的PCM转换成分组数据。 以这种方式，避免了串联声音编码布置。

公开(公告)号：US07734260B2

公开(公告)日：2010-06-08

申请号：US11622383

申请日：2007-01-11

申请人： Edward G. Tiedemann, Jr. ,  Lindsay A. Weaver, Jr. ,  Roberto Padovani

发明人： Edward G. Tiedemann, Jr. ,  Lindsay A. Weaver, Jr. ,  Roberto Padovani

IPC分类号： H04B1/04

CPC分类号： H04W74/0841 ,  H04B1/707 ,  H04B1/7103 ,  H04B7/2628 ,  H04B2201/709709 ,  H04J13/0022 ,  H04J13/10 ,  H04J13/16 ,  H04L1/188 ,  H04L1/1887 ,  H04W52/48 ,  H04W52/50 ,  H04W74/002 ,  H04W74/08 ,  H04W74/0833 ,  H04W74/0866

摘要： Collisions between messages simultaneously transmitted by multiple spread-spectrum transmitters are reduced by distributing the transmissions over the available resources of the receiver. Each mobile station in a CDMA system uses one or more randomization methods to distribute its transmissions. In the first randomization, the mobile station time-delays its transmissions by a number of chips of the PN code with which it spreads the transmitted signal. In a second randomization, the mobile station randomly selects the PN code. In a third randomization, the mobile station inserts a random delay between successive message transmissions or probes if it does not receive an acknowledgement after a predetermined timeout period. A predetermined number of such transmissions is called a probe sequence. In a fourth randomization, the mobile station inserts a relatively long random delay between successive probe sequences if it does not receive an acknowledgement of any probe in the sequence.

摘要翻译： 通过在接收机的可用资源上分发传输来减少由多个扩频发射机同时发送的消息之间的冲突。 CDMA系统中的每个移动站使用一种或多种随机化方法来分发其传输。 在第一次随机化中，移动台通过PN码的多个码片对其发送进行时间延迟，并通过该芯片扩展发送的信号。 在第二随机化中，移动台随机选择PN码。 在第三次随机化中，如果移动台在预定的超时时段之后没有接收到确认，则在连续的消息传输或探测之间插入随机延迟。 预定数量的这种传输被称为探测序列。 在第四随机化中，如果移动台在序列中没有接收到任何探测器的确认，则在连续探测序列之间插入相对长的随机延迟。

公开(公告)号：US5839052A

公开(公告)日：1998-11-17

申请号：US600103

申请日：1996-02-08

申请人： Richard F. Dean ,  Lindsay A. Weaver, Jr. ,  Charles E. Wheatley, III

发明人： Richard F. Dean ,  Lindsay A. Weaver, Jr. ,  Charles E. Wheatley, III

IPC分类号： H04N7/173

CPC分类号： H04L12/2801 ,  H04B3/54 ,  H04W52/325 ,  H04B2203/5441 ,  H04B2203/5487 ,  H04N7/10 ,  H04W36/18 ,  H04W52/146

摘要： The present invention is a method and apparatus for integrating a personal communication system with a cable television plant. A set of radio antenna devices (RAD) are connected to the cable plant. The RADs provide frequency conversion and power control of signal received from the cable plant for wireless transmission to the remote units. The RADs also provide power control and frequency conversion of wireless signals received from the remote units for transmission by the RADs onto the cable plant. In addition to the functions of standard base stations and centralized controller, the CATV base station must also compensate for gain variations in the cable plant. The downstream power control is regulated by a RAD reference signal which can be hidden within the CDMA signal for maximum efficiency. The upstream power control is regulated by an upstream gain reference signal which is individually transmitted by each RAD on the upstream link.

摘要翻译： 本发明是用于将个人通信系统与有线电视设备集成的方法和装置。 一组无线电天线设备（RAD）连接到电缆设备。 RAD提供从电缆设备接收的信号的频率转换和功率控制，用于无线传输到远程单元。 RAD还提供从远程单元接收的无线信号的功率控制和频率转换，以将RAD传输到电缆设备上。 除了标准基站和集中控制器的功能外，CATV基站还必须补偿电缆厂的增益变化。 下行功率控制由可以隐藏在CDMA信号内的RAD参考信号来调节，以获得最大的效率。 上游功率控制由上游链路上的每个RAD单独发送的上游增益参考信号来调节。

公开(公告)号：US5802105A

公开(公告)日：1998-09-01

申请号：US347526

申请日：1994-11-30

申请人： Edward G. Tiedemann, Jr. ,  Yu-Cheun Jou ,  Lindsay A. Weaver, Jr. ,  Gwain Bayley

发明人： Edward G. Tiedemann, Jr. ,  Yu-Cheun Jou ,  Lindsay A. Weaver, Jr. ,  Gwain Bayley

IPC分类号： H04L1/00 ,  H04B3/46 ,  H04B7/26 ,  H04B17/00 ,  H04L1/20 ,  H04L1/24 ,  H04L27/00 ,  H04L29/08 ,  H04L29/14

CPC分类号： H04L1/20 ,  H04L1/241 ,  H04L1/242 ,  H04L2027/0034

摘要： A system and method for testing signal transmission quality within a digital communication system is disclosed herein. The system may be incorporated within a digital cellular communication system in which information is exchanged over spread spectrum communication channels, among a plurality of mobile users, via at least one cell-site. The system contemplates testing a digital communication channel by transmitting a test sequence of digital data over the communication channel. The test sequence of digital data transmitted over the communication channel is received at a receiving station, within which is also generated a replica of the test sequence of digital data. The accuracy of transmission over the communication channel is then determined by comparing the replica of the test sequence of digital data to the test sequence of data received over the communication channel. The system allows the test sequence of digital data to be transmitted at one of a set of known data rates, with the receive station being disposed to identify the data rate associated with each test sequence of digital data. In a preferred implementation transmission of the test sequence involves generating a first plurality of data packets, which collectively comprise the test sequence of digital data. Each data packet is assigned one of a multiplicity of data rates in accordance with a first pseudorandom process, and is then transmitted at the data rate assigned thereto.

摘要翻译： 本文公开了一种用于测试数字通信系统内的信号传输质量的系统和方法。 该系统可以并入到数字蜂窝通信系统中，其中通过至少一个小区站点在多个移动用户之间通过扩频通信信道交换信息。 该系统考虑通过在通信信道上发送数字数据的测试序列来测试数字通信信道。 通过通信信道发送的数字数据的测试序列在接收站处被接收，在接收站中也产生数字数据的测试序列的副本。 然后通过将数字数据的测试序列的副本与通过通信信道接收的数据的测试序列进行比较来确定通信信道上的传输的准确性。 该系统允许数字数据的测试序列以一组已知数据速率中的一种传输，其中接收站被设置为识别与数字数据的每个测试序列相关联的数据速率。 在优选实施例中，测试序列的传输涉及生成第一多个数据分组，其共同地包括数字数据的测试序列。 每个数据分组根据第一伪随机过程分配多个数据速率中的一个，然后以分配给它的数据速率发送。

公开(公告)号：US5715236A

公开(公告)日：1998-02-03

申请号：US156757

申请日：1993-11-24

申请人： Klein S. Gilhousen ,  Irwin M. Jacobs ,  Roberto Padovani ,  Lindsay A. Weaver, Jr. ,  Charles E. Wheatley, III ,  Andrew J. Viterbi

发明人： Klein S. Gilhousen ,  Irwin M. Jacobs ,  Roberto Padovani ,  Lindsay A. Weaver, Jr. ,  Charles E. Wheatley, III ,  Andrew J. Viterbi

IPC分类号： H04B1/707 ,  H04B1/7075 ,  H04B1/709 ,  H04B1/7115 ,  H04B7/005 ,  H04B7/26 ,  H04J3/02 ,  H04J3/16 ,  H04J3/22 ,  H04J11/00 ,  H04J13/00 ,  H04J13/10 ,  H04J13/18 ,  H04L20060101 ,  H04L1/00 ,  H04L1/06 ,  H04L1/08 ,  H04L5/02 ,  H04L5/12 ,  H04L23/02 ,  H04L27/30 ,  H04W52/26

CPC分类号： H04L1/0002 ,  H04B1/3888 ,  H04B1/707 ,  H04B1/70757 ,  H04B1/709 ,  H04B7/2618 ,  H04B7/2628 ,  H04B7/2637 ,  H04J13/0022 ,  H04J13/0048 ,  H04J13/10 ,  H04J13/107 ,  H04J13/18 ,  H04L1/0006 ,  H04L1/0065 ,  H04L1/0068 ,  H04L1/0071 ,  H04L1/06 ,  H04L23/02 ,  H04L5/02 ,  H04L5/12 ,  H04B1/7115 ,  H04B2201/70701 ,  H04B2201/70703 ,  H04L1/0046 ,  H04L1/08 ,  H04W52/26 ,  Y02B60/31

摘要： A system and method for communicating information signals using spread spectrum communication techniques. PN sequences are constructed that provide orthogonality between the users so that mutual interference will be reduced, allowing higher capacity and better link performance. With orthogonal PN codes, the cross-correlation is zero over a predetermined time interval, resulting in no interference between the orthogonal codes, provided only that the code time frames are time aligned with each other. In an exemplary embodiment, signals are communicated between a cell-site and mobile units using direct sequence spread spectrum communication signals. In the cell-to-mobile link, pilot, sync, paging and voice channels are defined. Information communicated on the cell-to-mobile link channels are, in general, encoded, interleaved, bi-phase shift key (BPSK) modulated with orthogonal covering of each BPSK symbol along with quadrature phase shift key (QPSK) spreading of the covered symbols. In the mobile-to-cell link, access and voice channels are defined. Information communicated on the mobile-to-cell link channels are, in general, encoded, interleaved, orthogonal signalling along with QPSK spreading.

摘要翻译： 一种使用扩频通信技术传送信息信号的系统和方法。 构造PN序列，以提供用户之间的正交性，从而减少相互干扰，从而允许更高的容量和更好的链路性能。 对于正交PN码，在相关的时间间隔内，互相关为0，导致正交码之间没有干扰，只要码时间帧彼此时间对准。 在示例性实施例中，使用直接序列扩频通信信号在小区站点和移动单元之间传送信号。 在小区到移动链路中，定义了导频，同步，寻呼和语音信道。 在小区到移动链路信道上传送的信息通常是用每个BPSK符号的正交覆盖调制的编码，交织，双相移键（BPSK）以及覆盖符号的正交相移键（QPSK）扩展 。 在移动小区链路中，定义了接入和语音信道。 一般来说，在移动小区链路信道上传送的信息一起编码，交织，正交信令以及QPSK扩频。

公开(公告)号：US5504773A

公开(公告)日：1996-04-02

申请号：US171146

申请日：1993-12-21

申请人： Roberto Padovani ,  Edward G. Tiedemann, Jr. ,  Lindsay A. Weaver, Jr. ,  Brian K. Butler

发明人： Roberto Padovani ,  Edward G. Tiedemann, Jr. ,  Lindsay A. Weaver, Jr. ,  Brian K. Butler

IPC分类号： H04B1/707 ,  H04B1/7075 ,  H04B1/7115 ,  H04B7/005 ,  H04B7/26 ,  H04J3/16 ,  H04J3/22 ,  H04J3/24 ,  H04J11/00 ,  H04J13/00 ,  H04J13/18 ,  H04L1/00 ,  H04L1/08 ,  H04L5/02 ,  H04L5/12 ,  H04L7/04 ,  H04L23/02 ,  H04B1/69 ,  G06F11/00

CPC分类号： H04L1/0057 ,  H04B1/707 ,  H04B1/70757 ,  H04B7/2618 ,  H04B7/2628 ,  H04B7/2637 ,  H04J13/00 ,  H04J3/16 ,  H04J3/1688 ,  H04J3/22 ,  H04J3/24 ,  H04L1/0059 ,  H04L1/0065 ,  H04L1/0068 ,  H04L1/0071 ,  H04L1/08 ,  H04L23/02 ,  H04L5/02 ,  H04L5/12 ,  H04L7/048 ,  H04B1/7115 ,  H04B2201/70701 ,  H04B2201/70703 ,  H04J13/0048 ,  H04J13/18 ,  H04W52/26

摘要： In a digital communication system in which digital data is transmitted in data frames of a preselected time duration, a method and apparatus for formatting digital data in each data frame. A set of data bits of a first data type having a bit count corresponding to one of a plurality of predetermined bit counts are provided. A set of parity check bits for the set of data bits of said first data type are generated when the bit count is a highest bit count or a next to highest bit count. A set of tail bits is generated in accordance with a predetermined frame termination format. In respective order the set of data bits of the first data type, the parity check bits, and the tail bits are porovided in a data frame if the bit count is of the highest bit count or of the next to highest bit count. Otherwise, the set of data bits of the first data type and the tail bits are provided in respective order in the data frame.

摘要翻译： 在数字数据在预选持续时间的数据帧中发送的数字通信系统中，在每个数据帧中格式化数字数据的方法和装置。 提供具有对应于多个预定位计数之一的位计数的第一数据类型的一组数据位。 当比特计数是最高比特数或下一个最高比特数时，产生用于所述第一数据类型的数据比特组的一组奇偶校验位。 根据预定的帧终止格式生成一组尾比特。 如果比特数是最高比特数或下一个到最高比特数，则在相应的顺序中，如果第一数据类型，奇偶校验位和尾比特的数据比特的数据比特被排列在数据帧中。 否则，在数据帧中以相应的顺序提供第一数据类型和尾比特的数据比特组。

公开(公告)号：US5142278A

公开(公告)日：1992-08-25

申请号：US620133

申请日：1990-11-30

申请人： Kamran Moallemi ,  Franklin P. Antonio ,  Daniel K. Butterfield ,  Lindsay A. Weaver, Jr.

发明人： Kamran Moallemi ,  Franklin P. Antonio ,  Daniel K. Butterfield ,  Lindsay A. Weaver, Jr.

IPC分类号： B61L15/00 ,  G08G1/127

CPC分类号： B61L15/0036 ,  B61L15/0072 ,  G08G1/127

摘要： An apparatus and method for providing communication of information between a truck tractor and trailer via existing truck wiring. At least one transmitter is located in each trailer for generating a unique identification signal representative of trailer identification information corresponding to the trailer in which the transmitter is located, modulating the identification signal, and providing the modulated identification on an existing truck power bus coupling the tractor and trailer. A receiver is located in the tractor for receiving each modulated identification signal on the power bus, demodulating each modulated identification signal and providing each demodulated identification signal to a mobile communications terminal located in the tractor for transmission to a central facility. The system may further include the transmission of trailer status or load status information by the transmitter to the receiver in a similar manner as the identification information.

摘要翻译： 一种用于通过现有卡车配线提供卡车拖拉机和拖车之间的信息通信的装置和方法。 至少一个发射器位于每个拖车中，用于产生代表对应于发射机所在的预告片的拖车识别信息的唯一标识信号，调制识别信号，以及将耦合拖拉机的现有卡车电力总线上的调制标识提供 和拖车。 接收机位于拖拉机中，用于接收电力总线上的每个调制的识别信号，解调每个调制的识别信号，并将每个解调的识别信号提供给位于拖拉机中的移动通信终端，以便传输到中央设施。 该系统可以进一步包括发射机以与识别信息相似的方式向接收机发送拖车状态或负载状态信息。

公开(公告)号：US4979170A

公开(公告)日：1990-12-18

申请号：US145176

申请日：1988-01-19

申请人： Klein S. Gilhousen ,  Franklin P. Antonio ,  Irwin M. Jacobs ,  Lindsay A. Weaver, Jr.

发明人： Klein S. Gilhousen ,  Franklin P. Antonio ,  Irwin M. Jacobs ,  Lindsay A. Weaver, Jr.

IPC分类号： G02B6/293 ,  G02B6/34 ,  G02B6/42 ,  H01S3/08 ,  H01S5/14 ,  H01S5/40 ,  H04B1/7136 ,  H04B7/212 ,  H04B10/155 ,  H04L5/16

CPC分类号： H04B1/7136 ,  G02B6/12007 ,  G02B6/2931 ,  G02B6/29328 ,  G02B6/29383 ,  G02B6/4206 ,  G02B6/4246 ,  G02B6/4249 ,  G02B6/425 ,  H01S3/08009 ,  H01S5/141 ,  H04B10/506 ,  H04B7/212 ,  H04L5/16 ,  G02B6/29334 ,  H01S5/4025 ,  H01S5/4062 ,  H01S5/4087

摘要： A message communication system employing one or more centralized communication stations transferring messages through Earth orbit repeater satellites to or from mobile terminals with at least one central communication station having a first transceiver for transmitting a first communication signal to one or more mobile terminals and at least one mobile terminal having a second transceiver for receiving the first communication signal and demodulating it, and for transmitting at a predetermined duty cycle of the second transceiver, a second communication signal to at least one of the central communication stations. The preferred duty cycle over which the second communication signal is transmitted is about fifty percent of the second transceiver duty cycle. The communication system uses Time Division Multiplexed (TDM) communication signals using a number of channels as designated address channels with the remainder being used for data transfer. Information transmitted on the address channels is used by terminals to determine both the presence of a message and its corresponding data transmission or reception channel. In addition the terminals use the reception of the first communication signal to adjust return link transmission frequency to compensate for transmission path errors. The alternating duty cycle allows mobile terminals to use a single set of local oscillators for both transmission and reception modes of operation. To decrease interference with other systems the present system employs a power dispersal modulation function to achieve the footprint of a video signal for high transfer rate digital communication signals.

摘要翻译： 一种消息通信系统，其采用一个或多个集中式通信站，其中至少一个中央通信站通过地​​球轨道中继卫星向移动终端传送消息，所述至少一个中央通信站具有用于将第一通信信号发送到一个或多个移动终端的第一收发器和至少一个 移动终端具有用于接收第一通信信号并对其进行解调的第二收发器，并且用于以第二收发器的预定占空比发送第二通信信号到至少一个中央通信站。 发送第二通信信号的优选占空比大约是第二收发器占空比的百分之五十。 通信系统使用时分复用（TDM）通信信号，使用多个信道作为指定地址信道，其余部分用于数据传输。 在地址信道上发送的信息被终端用于确定消息的存在及其对应的数据发送或接收信道。 此外，终端使用第一通信信号的接收来调整返回链路传输频率以补偿传输路径错误。 交替占空比允许移动终端在传输和接收操作模式下使用单组本地振荡器。 为了减少与其他系统的干扰，本系统采用功率分散调制功能来实现高传输速率数字通信信号的视频信号的覆盖区。

公开(公告)号：US07426391B2

公开(公告)日：2008-09-16

申请号：US11622403

申请日：2007-01-11

申请人： Edward G. Tiedemann, Jr. ,  Lindsay A. Weaver, Jr. ,  Roberto Padovani

发明人： Edward G. Tiedemann, Jr. ,  Lindsay A. Weaver, Jr. ,  Roberto Padovani

IPC分类号： H04Q7/20

CPC分类号： H04W74/0841 ,  H04B1/707 ,  H04B1/7103 ,  H04B7/2628 ,  H04B2201/709709 ,  H04J13/0022 ,  H04J13/10 ,  H04J13/16 ,  H04L1/188 ,  H04L1/1887 ,  H04W52/48 ,  H04W52/50 ,  H04W74/002 ,  H04W74/08 ,  H04W74/0833 ,  H04W74/0866

摘要： Collisions between messages simultaneously transmitted by multiple spread-spectrum transmitters are reduced by distributing the transmissions over the available resources of the receiver. Each mobile station in a CDMA system uses one or more randomization methods to distribute its transmissions. In the first randomization, the mobile station time-delays its transmissions by a number of chips of the PN code with which it spreads the transmitted signal. In a second randomization, the mobile station randomly selects the PN code. In a third randomization, the mobile station inserts a random delay between successive message transmissions or probes if it does not receive an acknowledgement after a predetermined timeout period. A predetermined number of such transmissions is called a probe sequence. In a fourth randomization, the mobile station inserts a relatively long random delay between successive probe sequences if it does not receive an acknowledgement of any probe in the sequence.

摘要翻译： 通过在接收机的可用资源上分发传输来减少由多个扩频发射机同时发送的消息之间的冲突。 CDMA系统中的每个移动站使用一种或多种随机化方法来分发其传输。 在第一次随机化中，移动台通过PN码的多个码片对其发送进行时间延迟，并通过该芯片扩展发送的信号。 在第二随机化中，移动台随机选择PN码。 在第三随机化中，如果移动台在预定的超时时段之后没有接收到确认，则在连续的消息传输或探测之间插入随机延迟。 预定数量的这种传输被称为探测序列。 在第四随机化中，如果移动台在序列中没有接收到任何探测器的确认，则在连续探测序列之间插入相对长的随机延迟。