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662 条记录 (耗时 0.027 秒)

    DTMF signal receiving circuit
    91.
    发明授权
    DTMF signal receiving circuit 失效
    DTMF信号接收电路

    公开(公告)号：US5459785A

    公开(公告)日：1995-10-17

    申请号：US098907

    申请日：1993-07-29

    申请人： Mitsuhiko Noda

    发明人： Mitsuhiko Noda

    IPC分类号： H04L27/30 ,  H04Q1/453 ,  H04Q1/46 ,  H04M11/08

    CPC分类号： H04Q1/46 ,  H04L27/30 ,  H04Q1/453

    摘要： A DTMF signal receiving circuit which is capable of freely selecting a frequency of a received dial tone signal. The DTMF signal receiving circuit receives a DTMF signal, decodes the DTMF signal, and outputs the signal as the decoding result. The DTMF signal receiving circuit comprises a dial tone signal detecting circuit for freely selecting a frequency of a dial tone signal which is the object of detection in accordance with a supplied selection signal, and a judging circuit for judging whether or not the signal as the result of detection of the DTMF signal is output on the basis of the output of the dial tone signal detecting circuit.

    摘要翻译： 一种DTMF信号接收电路，其能够自由选择所接收的拨号音信号的频率。 DTMF信号接收电路接收DTMF信号，对DTMF信号进行解码，并输出该信号作为解码结果。 DTMF信号接收电路包括拨号音信号检测电路，用于根据所提供的选择信号自由选择作为检测对象的拨号音信号的频率，以及用于判断作为结果的信号的判断电路 基于拨号音信号检测电路的输出输出DTMF信号的检测。

    Path gain estimation in a receiver
    92.
    发明授权
    Path gain estimation in a receiver 失效
    接收机中的路径增益估计

    公开(公告)号：US5442661A

    公开(公告)日：1995-08-15

    申请号：US106250

    申请日：1993-08-13

    申请人： David D. Falconer

    发明人： David D. Falconer

    IPC分类号： H04B1/7093 ,  H04B1/7115 ,  H04B1/7117 ,  H04B7/00 ,  H04L27/30 ,  H04B1/69

    CPC分类号： H04B1/7115 ,  H04B1/7093 ,  H04B1/7117

    摘要： A coherent RAKE receiver utilizes a "blind block" path gain estimation scheme, based on a maximum likelihood criterion, to estimate path gains in the receiver. It is "blind" in that preliminary hard decisions on coded bits (i.e., coded bits from the corrupt transmitted signal) are not used. Instead, a form of soft decisions are used. It is a "block" scheme in that the complex path gains are estimated for an isolated block, for example a block of B correlator outputs. The path gains varying with time are approximated to be linear in time such that the average path gain and the slope of the path gain per path can be utilized to estimate the path gain. The path gain estimation scheme overcomes the shortcomings of typical CDMA systems where there is no assurance of continuous transmission (except for full-rate 9600 b/s transmission) upon which to base a FIR filter-type prediction scheme.

    摘要翻译： 相干RAKE接收机利用基于最大似然准则的“盲块”路径增益估计方案来估计接收机中的路径增益。 因为不使用对编码比特（即来自损坏的发送信号的编码比特）的初步硬判决是“盲”的。 相反，使用一种软的决定。 这是一个“块”方案，因为对于一个隔离块估计了复杂路径增益，例如一个B相关器输出块。 随时间变化的路径增益近似为时间线性，使得平均路径增益和每条路径的路径增益的斜率可以用于估计路径增益。 路径增益估计方案克服了基于FIR滤波器类型预测方案的典型CDMA系统的缺点，其中不能保证连续传输（全速率9600b / s传输除外）。

    Broadcast synchronized communication system
    93.
    发明授权
    Broadcast synchronized communication system 失效
    广播同步通信系统

    公开(公告)号：US5442652A

    公开(公告)日：1995-08-15

    申请号：US188324

    申请日：1994-01-25

    申请人： Allen G. Jacobson

    发明人： Allen G. Jacobson

    IPC分类号： H04H20/31 ,  H04H60/23 ,  H04H60/91 ,  H04L27/30 ,  H04L9/12

    CPC分类号： H04H20/31 ,  H04H60/23 ,  H04H60/91

    摘要： A communication system in accordance with the invention employs a broadcast signal for synchronization of the transmitters and receivers in the system without use of a special base transmitter for synchronizing signal transmissions. Each transmitter having a pre-assigned time slot counts from a synchronizing index which is inherent in or added to the broadcast signal to determine when to transmit. The receiver of receivers similarly count from the synchronizing index to determine when to look for specific time slice transmissions.

    摘要翻译： 根据本发明的通信系统采用用于系统中的发射机和接收机的同步的广播信号，而不使用用于同步信号传输的专用基站发射机。 具有预分配时隙的每个发射机从广播信号中固有或相加的同步索引计数，以确定何时发送。 接收机的接收机类似地从同步索引计数，以确定何时寻找特定的时间片传输。

    Reduced interference through offset frequency partitioning
    94.
    发明授权
    Reduced interference through offset frequency partitioning 失效
    通过偏移频率分割减少干扰

    公开(公告)号：US5430761A

    公开(公告)日：1995-07-04

    申请号：US250306

    申请日：1994-05-27

    申请人： Eugene J. Bruckert ,  Michael D. Kotzin

    发明人： Eugene J. Bruckert ,  Michael D. Kotzin

    IPC分类号： H04B7/26 ,  H04J4/00 ,  H04W16/02 ,  H04W16/12 ,  H04L27/30

    CPC分类号： H04W16/12 ,  H04B7/2643 ,  H04J4/00 ,  H04W16/02

    摘要： A method of reducing interference within a cellular system (10) by partitioning a designated frequency spectrum within a service coverage area (.0.1, .0.2, or .0.3) into a first and at least second spectrum inclusive of the designated frequency spectrum, each with an associated power level, and offsetting the spectrums for each TDM frame under the control of an offset number unique to each TDM frame. Assignment of communication units to a spectrum and power level are based upon distance from the base site (as determined through signal strength measurements). The spectral content of spectrums in adjacent service coverage areas is adjusted to include non-coincidental frequencies.

    摘要翻译： 一种通过将服务覆盖区域（O1，O2或O3）内的指定频谱划分成包括指定频谱在内的第一和至少第二频谱中来减少蜂窝系统（10）内的干扰的方法， 功率电平，并且在每个TDM帧唯一的偏移号的控制下抵消每个TDM帧的频谱。 将通信单元分配到频谱和功率电平是基于距离基站的距离（通过信号强度测量确定的）。 相邻服务覆盖区域中的频谱的频谱内容被调整为包括不一致的频率。

    Low-power frequency-hopped spread spectrum reverse paging system
    95.
    发明授权
    Low-power frequency-hopped spread spectrum reverse paging system 失效
    低功率跳频扩频反向寻呼系统

    公开(公告)号：US5430759A

    公开(公告)日：1995-07-04

    申请号：US158441

    申请日：1993-11-24

    申请人： Hanoch Yokev ,  Haim Harel ,  Yehouda Meiman

    发明人： Hanoch Yokev ,  Haim Harel ,  Yehouda Meiman

    IPC分类号： G01S1/02 ,  G01S3/02 ,  G01S3/04 ,  G01S3/10 ,  G01S5/00 ,  G01S5/02 ,  G01S5/04 ,  G01S19/25 ,  G01S19/27 ,  H04B1/713 ,  H04B1/7156 ,  H04B7/26 ,  H04W64/00 ,  H04W84/02 ,  H04W88/02 ,  H04L27/30

    CPC分类号： H04W64/00 ,  G01S1/026 ,  G01S3/023 ,  G01S3/043 ,  G01S3/10 ,  G01S5/0009 ,  G01S5/021 ,  G01S5/04 ,  H04B1/713 ,  H04B1/7156 ,  H04B7/2681 ,  H04B7/2693 ,  H04L5/0053 ,  H04W84/025 ,  H04L5/0007 ,  H04L5/0062 ,  H04L5/0091 ,  H04W88/022

    摘要： An acknowledgement paging system is described which fits within the existing infrastructure of a paging network and which provides low cost manufacture and low power operation while still enabling the acknowledgement paging over long distances. The acknowledgement paging system consists of a standard paging transmitter and a plurality of remote paging units which respond to a page using frequency-hopped spread-spectrum differential bi-phase shift keying communications. The plurality of pagers are assigned to groups with each group being assigned a separate starting location in a common, repeating pseudo-random noise code which determines the frequency hops. The grouping of pagers minimizes the collisions of acknowledgment transmissions between groups and the enables a large number of paging units to operate within a single geographic area. The pagers include a special double loop PLL synthesizer to produce an accurate narrow band frequency and to change or hop frequencies in a rapid fashion. The base receiving unit employs special algorithms for retrieving very low power acknowledgement paging messages in a noisy environment by using data redundancy, data interleaving, soft decoding and error correction codes to strip the bi-phase-modulated, frequency-hopped spread-spectrum digital data transmitted from the remote pocket pagers. A history of the frequency and phase drift is used during reception of the acknowledgement messages to predict the phase and frequency drift of the encoded digital information to further reduce decoding error. Signal to noise ratios are determined for each frequency hop and relatively noisy hops are discarded or minimized in a soft decoding process based redundancy of data bits.

    摘要翻译： 描述了一种确认寻呼系统，其适合于寻呼网络的现有基础设施，并且在远距离执行确认寻呼的同时提供低成本的制造和低功率操作。 确认寻呼系统由标准寻呼发射机和使用跳频扩频差分双相移键控通信响应寻呼的多个远程寻呼单元组成。 多个寻呼机被分配给组，其中每个组被分配在确定跳频的公共重复伪随机噪声码中的单独的起始位置。 寻呼机的分组使组之间的确认传输的冲突最小化，并且使得大量寻呼单元能够在单个地理区域内操作。 寻呼机包括一个特殊的双回路PLL合成器，以产生精确的窄带频率，并以快速方式改变或跳频。 基站接收单元采用特殊算法，通过使用数据冗余，数据交织，软解码和纠错码来消除双相调制的跳频扩频数字数据，在噪声环境中检索极低功率的确认寻呼消息 从远程口袋传呼机传输。 在接收确认消息期间使用频率和相位漂移的历史来预测编码的数字信息的相位和频率漂移以进一步减少解码错误。 针对每个跳频确定信噪比，并且在基于软解码过程的数据比特冗余中丢弃或最小化相对噪声的跳。

    Modified Chirp-Z pulse detector
    98.
    发明授权
    Modified Chirp-Z pulse detector 失效
    改进型Chirp-Z脉冲检测器

    公开(公告)号：US5388121A

    公开(公告)日：1995-02-07

    申请号：US233561

    申请日：1994-04-25

    申请人： William J. Skudera, Jr.

    发明人： William J. Skudera, Jr.

    IPC分类号： H04L27/00 ,  H04L27/30

    CPC分类号： H04L27/00

    摘要： A circuit is disclosed for deriving a modified Chirp-Z transform that focs on a narrow bandwidth within a solitary time interval and thereby assures RF pulse detection with the characteristic gain of conventional Chirp-Z transforms. RF pulse detection bandwidth enhancement is accomplished with this circuit by arranging it in a plurality of parallel channels which each relate to one RF pulse frequency within that bandwidth.

    摘要翻译： 公开了一种用于导出改进的Chirp-Z变换的电路，其侧重于孤立时间间隔内的窄带宽，从而通过常规Chirp-Z变换的特征增益确保RF脉冲检测。 RF脉冲检测带宽增强是通过将其布置在多个并行通道中来实现的，每个并行通道与该带宽内的一个RF脉冲频率相关。

    Communication system
    99.
    再颁专利
    Communication system 失效
    通讯系统

    公开(公告)号：USRE34831E

    公开(公告)日：1995-01-17

    申请号：US132158

    申请日：1993-10-05

    申请人： Van Metre Lund

    发明人： Van Metre Lund

    IPC分类号： H04B1/69 ,  H04B1/707 ,  H04J13/00 ,  H04L27/30

    CPC分类号： H04L27/30 ,  H04B1/69 ,  H04B1/707 ,  H04J13/00

    摘要： In a spread spectrum communication system, sequence signals are developed in both a transmitter and receiver, in each case being derived from a clock signal through digital count-down and logic circuitry including a programmable counter which receives control number defining groups of signals from a memory under control of an indexing counter. A sequence signal in the transmitter is applied through a filter to produce a filtered signal which is propagated as a sequence of variations of alternating polarity with predetermined varying durations occurring in a predetermined distinctive order. A received signal and sequence signal of the same form as in the transmitter are applied to a product detector the output of which is applied to an integrator. Loop circuitry is provided for synchronizing the generation of the sequence signal in the receiver with that in the transmitter. A plurality of channels may be provided, using common synchronizing and other circuitry.

    摘要翻译： 在扩展频谱通信系统中，序列信号在发射机和接收机两者中都被开发，在每种情况下都是通过数字递减计数和从逻辑电路得到的逻辑电路，包括可编程计数器，该可编程计数器从存储器接收定义信号组的控制数 在索引计数器的控制下。 发射机中的序列信号通过滤波器施加以产生经过滤波的信号，该滤波信号作为交变极性的变化序列传播，并以预定的不同顺序发生预定的变化持续时间。 与发射机相同形式的接收信号和序列信号被应用于产品检测器，其输出应用于积分器。 环路电路用于使接收机中的序列信号与发射机中的序列信号的产生同步。 可以使用公共同步和其它电路来提供多个信道。

    Method and apparatus for frequency hopping a signalling channel in a communication system
    100.
    发明授权
    Method and apparatus for frequency hopping a signalling channel in a communication system 失效
    用于在通信系统中跳频信令信道的方法和装置

    公开(公告)号：US5381443A

    公开(公告)日：1995-01-10

    申请号：US955793

    申请日：1992-10-02

    申请人： David E. Borth ,  John R. Haug ,  Phillip D. Rasky

    发明人： David E. Borth ,  John R. Haug ,  Phillip D. Rasky

    IPC分类号： H04B7/26 ,  H04W74/04 ,  H04L27/30

    CPC分类号： H04B7/2643 ,  H04W74/002

    摘要： A cellular communication system hops both signalling channels and traffics channels in a common hopping sequence. To obtain system information from the frequency hopping signalling channel, a subscriber unit waits on a predetermined frequency, or carrier, until the frequency hopped signalling channel arrives at the predetermined frequency. Once arrived, the subscriber unit obtains synchronization information, and information related to the hopping sequence, from the signalling channel during the hop. The subscriber unit may then hop in tandem with the system, obtaining further system information in subsequent hops. The cellular communication system supports mobile assisted handoff (MAHO) by allowing a subscriber unit to measure signalling channel of neighboring cells in a similar manner, and using the measurements to assist in communication handoff from a source cell to a neighboring cell.

    摘要翻译： 蜂窝通信系统在公共跳频序列中跳过信令信道和业务信道。 为了从跳频信令信道获得系统信息，用户单元等待预定频率或载波，直到跳频信令信道到达预定频率。 一旦到达，用户单元在跳跃期间从信令信道获得同步信息和与跳频序列相关的信息。 用户单元然后可以与系统一起跳转，在随后的跳数中获得进一步的系统信息。 蜂窝通信系统通过允许用户单元以类似的方式测量相邻小区的信令信道，并且使用这些测量来帮助从源小区到相邻小区的通信切换来支持移动辅助切换（MAHO）。