-
1.发明授权公开(公告)号：US06611493B1
公开(公告)日：2003-08-26
申请号：US09236601
申请日：1999-01-26
申请人： Atsushi Miyashita , Toshiyuki Akiyama , Seiichi Sano , Hiroyuki Takesue , Tatuhiro Nakada , Nobuo Tsukamoto
发明人： Atsushi Miyashita , Toshiyuki Akiyama , Seiichi Sano , Hiroyuki Takesue , Tatuhiro Nakada , Nobuo Tsukamoto
IPC分类号： H04J1100
CPC分类号： H04L27/2608
摘要： A communication method in an orthogonal frequency division multiplexing modulation communication system includes a transmission apparatus in which a frequency bandwidth of a signal modulated in accordance with an orthogonal frequency division multiplexing modulation system is changed and the modulated signal is transmitted and a receiving apparatus in which the modulated signal is received and a frequency bandwidth for demodulation of the received signal is changed to follow the change of the frequency bandwidth of the modulated signal.
摘要翻译： 正交频分复用调制通信系统中的通信方法包括：发送装置，其中根据正交频分复用调制方式调制的信号的频率带宽被改变，并且调制信号被发送;以及接收装置，其中， 接收到调制信号，并且改变接收信号的解调频率带宽以跟随调制信号的频率带宽的变化。
-
2.发明授权公开(公告)号：US06473466B1
公开(公告)日：2002-10-29
申请号：US09206406
申请日：1998-12-07
IPC分类号： H04B720
CPC分类号： H04B7/0608 , H04L1/0001 , H04L2025/03694
摘要： A data transmitting apparatus in which in an antenna switching of the data transmitting apparatus, a sudden change of transmission path characteristics is prevented and a state where an automatic equalizing function on the reception side can follow can be held. The apparatus has a processing circuit for gradually switching antennas of the data transmitting apparatus with respect to the time and for continuously switching one antenna from the rated level to the 0 level and for continuously switching the other antenna from the 0 level to the rated level. The apparatus operates so as to always keep the optimum constellation state in which the automatic equalizing process follows.
摘要翻译： 一种数据发送装置，其中在数据发送装置的天线切换中防止传输路径特性的突然变化，并且可以保持接收侧的自动均衡功能能够跟随的状态。 该装置具有处理电路，用于相对于时间逐渐切换数据发送装置的天线，并且将一个天线从额定电平连续地切换到0电平，并且将另一个天线从0电平连续地切换到额定电平。 该装置操作以便始终保持自动均衡处理遵循的最佳星座状态。
-
3.发明授权公开(公告)号：US06381236B1
公开(公告)日：2002-04-30
申请号：US09236602
申请日：1999-01-26
IPC分类号： H04J100
CPC分类号： H04L5/1484 , H04L5/023
摘要： A bi-directional digital transmission method, and system, for sending and receiving digital transmission signals having a frame configuration modulated by an orthogonal frequency division multiplex modulation scheme. A first sending unit in a first transmission station converts first continuous data to a up-direction intermittent transmission signal, and sends it from a first antenna via a first switchover unit. The up-direction intermittent transmission signal is received by a second antenna of a second transmission station, and supplied to a second receiving unit of the second transmission station via a second switchover unit of the second transmission station. The second receiving unit determines whether receiving operation of the up-direction intermittent transmission signal has been established, and if so, restores the original first continuous data. A second sending unit in the second transmission station converts second continuous data to a down-direction intermittent transmission signal, and sends it from a second antenna via a second switchover unit. In the first transmission station, the down-direction intermittent sending transmission signal is received by the first antenna, and supplied to a first receiving unit via the first switchover unit to restore the original second continuous data.
摘要翻译： 一种用于发送和接收具有由正交频分复用调制方案调制的帧配置的数字传输信号的双向数字传输方法和系统。 第一发送站中的第一发送单元将第一连续数据转换为上行间歇发送信号，并经由第一切换单元从第一天线发送。 上行间歇发送信号由第二发送站的第二天线接收，经由第二发送站的第二切换单元提供给第二发送站的第二接收单元。 第二接收单元确定上行间歇发送信号的接收操作是否已经建立，如果是，则恢复原始的第一连续数据。 第二发送站中的第二发送单元将第二连续数据转换为下行间歇发送信号，经由第二切换单元从第二天线发送。 在第一发送站中，向下方向间歇发送发送信号由第一天线接收，经由第一切换单元提供给第一接收单元，恢复原来的第二连续数据。
-
4.发明授权Data transmission system, data transmission communication station, and data transmission method 失效数据传输系统，数据传输通信站和数据传输方式公开(公告)号：US06813326B1
公开(公告)日：2004-11-02
申请号：US09394276
申请日：1999-09-10
申请人： Atsushi Miyashita , Toshiyuki Akiyama , Seiichi Sano , Hisao Koda , Itsuo Ishida , Hiroyuki Takesue , Tatsuhiro Nakada , Nobuo Tsukamoto
发明人： Atsushi Miyashita , Toshiyuki Akiyama , Seiichi Sano , Hisao Koda , Itsuo Ishida , Hiroyuki Takesue , Tatsuhiro Nakada , Nobuo Tsukamoto
IPC分类号： H04L704
摘要： A data transmission system for transmitting data from a transmitter to a receiver located away therefrom. The transmitter includes circuitry for transmitting together a main signal having a carrier modulated with main data to be transmitted and as well as a sub-signal to be used in frequency conversion and generated by modulating a carrier of a predetermined frequency out of a frequency band of the main signal. The receiver includes circuitry for receiving a receive signal from the transmitter and extracting the sub-signal therefrom and also includes circuitry for generating a signal to be used as a reference at the time of converting the receive signal to a signal having a predetermined frequency on the basis of the extracted sub-signal.
摘要翻译： 一种数据传输系统，用于将数据从发射机发射到远离其的接收机。 发射机包括用于将具有被发送的主数据调制的载波的主信号和用于频率转换的子信号一起发送的电路，并且通过调制来自频率的频带中的预定频率的载波 主要信号。 接收机包括用于从发射机接收接收信号并从其中提取子信号的电路，还包括用于产生在将接收信号转换成具有预定频率的信号时用作参考的信号的电路， 提取的子信号的基础。
-
公开(公告)号：US06512798B1
公开(公告)日：2003-01-28
申请号：US09262840
申请日：1999-03-05
IPC分类号： H04L512
CPC分类号： H04L27/2071 , H04L25/03834
摘要： A digital signal communication system includes a transmission circuit or a receiving circuit for digitally transmitting two types of signals by orthogonal modulation. The transmission circuit includes an orthogonal modulator and a nonrecursive digital low-pass filter having the same frequency characteristic as a predetermined frequency characteristic of the output signal of the orthogonal modulator. The receiving circuit includes an orthogonal demodulator and a nonrecursive digital low-pass filter having the same frequency characteristic as a predetermined frequency characteristic of the output signal of the orthogonal demodulator. The total number of taps required for determining the frequency characteristic of the nonrecursive digital low-pass filter is set to H, and the series of tap coefficients is set as C1, C2, C3, . . . , CH, where H is an arbitrary positive integer of not less than 2. The nonrecursive digital low-pass filters include a first low-pass filter for filtering one of the two types of signal and a second low-pass filter for filtering the other type of the signal. The first low-pass filter has taps about one half of H including a tap coefficient series C1, C3, C5, . . . , CODD, and the second low-pass filter has taps about one half of H including a tap coefficient series C2, C4, C6, . . . , CEVEN.
摘要翻译： 数字信号通信系统包括用于通过正交调制数字地发送两种类型的信号的发送电路或接收电路。 发送电路包括具有与正交调制器的输出信号的预定频率特性相同的频率特性的正交调制器和非递归数字低通滤波器。 接收电路包括具有与正交解调器的输出信号的预定频率特性相同的频率特性的正交解调器和非递归数字低通滤波器。 用于确定非递归数字低通滤波器的频率特性所需的抽头总数设置为H，并且抽头系数串被设置为C1，C2，C3。 。 。 ，CH，其中H是不小于2的任意正整数。非递归数字低通滤波器包括用于对两种类型的信号中的一种进行滤波的第一低通滤波器和用于滤除另一种信号的第二低通滤波器 信号类型。 第一个低通滤波器具有大约H的一半的抽头，包括抽头系数C1，C3，C5。 。 。 ，CODD，第二低通滤波器具有大约H的一半的抽头，包括抽头系数C2，C4，C6。 。 。 ，CEVEN。
-
6.发明授权OFDM modulator and OFDM modulation method for digital modulated wave having guard interval 失效具有保护间隔的数字调制波的OFDM调制器和OFDM调制方法公开(公告)号：US06304611B1
公开(公告)日：2001-10-16
申请号：US09099390
申请日：1998-06-18
IPC分类号： H04K110
CPC分类号： H04L27/2607 , H04L27/2626
摘要： An orthogonal frequency division multiplex (OFDM) modulator of such a system as to add guard intervals to a temporal waveform generated by modulating an input data train into a large number of (sub)carriers, conducting quadrature modulation, and outputting an OFDM signal. The OFDM modulator includes an IFFT circuit for conducting inverse fast Fourier transform processing to modulate the input data train into a large number of (sub)carriers, a guard interval adder for adding a guard interval to each effective symbol duration of a composite carrier signal supplied from the IFFT circuit and outputting a resultant signal, a control signal generator for generating, in synchronism with each guard interval of the composite carrier signal having the guard intervals added thereto, such a control signal as to attenuate signal amplitude of the composite carrier signal over an interval substantially equal in length to each guard interval; and an amplitude controller, responsive to the control signal, to attenuate the amplitude of the composite carrier signal supplied from the guard interval adder and output a resultant signal, only over an interval substantially equal in length to each guard interval. The amplitude controller outputting, in remaining intervals, the composite carrier signal supplied from the guard interval adder as it is.
摘要翻译： 这种系统的正交频分复用（OFDM）调制器，用于通过将输入数据串调制成大量（子）载波，进行正交调制并输出OFDM信号而产生的时间波形增加保护间隔。 OFDM调制器包括用于进行快速傅立叶逆变换逆变换处理以将输入数据串调制成大量（子）载波的IFFT电路，用于将提供的复合载波信号的每个有效符号持续时间加上保护间隔的保护间隔加法器 从IFFT电路输出结果信号，控制信号发生器，与与其相加的保护间隔的复合载波信号的每个保护间隔同步地产生一个控制信号，以便衰减复合载波信号的信号幅度 长度与每个保护间隔基本相等的间隔; 以及振幅控制器，响应于控制信号，衰减从保护间隔加法器提供的复合载波信号的振幅，并输出结果信号，仅在长度上与每个保护间隔基本相等的间隔上。 幅度控制器以剩余的间隔输出从保护间隔加法器原样提供的复合载波信号。
-
7.发明授权Method of an apparatus for demodulating amplitude-modulated signals in an amplitude phase shift keying (APSK) system 失效一种在幅度相移键控（APSK）系统中解调幅度调制信号的装置的方法
公开(公告)号：US6046629A
公开(公告)日：2000-04-04
申请号：US96455
申请日：1998-06-11
申请人： Toshiyuki Akiyama , Atsushi Miyashita , Seiichi Sano , Nobuo Tsukamoto , Shigeki Moriyama , Kenichi Tsuchida
发明人： Toshiyuki Akiyama , Atsushi Miyashita , Seiichi Sano , Nobuo Tsukamoto , Shigeki Moriyama , Kenichi Tsuchida
CPC分类号： H04L27/389
摘要： In a demodulating method of demodulating amplitude-demodulated signals in an amplitude phase shift keying system for conducting an amplitude modulation by setting signal points as information codes on a complex plane representing a signal space of transmission signals onto circumferences of two concentric circles including a first circle having a first diameter and a second circle having a second diameter smaller than the first diameter on the complex plane, there are obtained, in accordance with an amplitude value of an amplitude component of each symbol of a received amplitude-modulated signal, a first threshold value and a second threshold value having a predetermined relationship with the amplitude value. Next, the amplitude value the an amplitude component of each symbol of the successively received amplitude-modulated signal is compared with the first and second first threshold values to determine an amplitude variation in the amplitude component of each symbol in accordance with a result from the comparison so as to output therefrom a signal representing the determination result as a code obtained by demodulating the amplitude component.
摘要翻译： 在解调幅度相移键控系统中的幅度解调信号的解调方法中，用于通过将表示发送信号的信号空间的信号空间的信号点设置为信号点进行幅度调制，以将发送信号的信号空间设置在包括第一圆周的两个同心圆的周围 具有第一直径和第二直径小于复平面上的第一直径的第二直径，根据接收到的幅度调制信号的每个符号的振幅分量的振幅值，获得第一阈值 值和与振幅值具有预定关系的第二阈值。 接下来，将连续接收的幅度调制信号的每个符号的振幅分量的振幅值与第一和第二第一阈值进行比较，以根据比较结果确定每个符号的幅度分量的振幅变化 从而从其输出表示确定结果的信号作为通过解调幅度分量而获得的代码。
-
8.发明授权公开(公告)号：US06381251B1
公开(公告)日：2002-04-30
申请号：US09096454
申请日：1998-06-11
IPC分类号： H04J100
CPC分类号： H04L27/2662 , H04L27/2602 , H04L27/2675
摘要： A data transmission apparatus of an orthogonal frequency multiplex modulation system wherein data is transmitted using a plurality of carriers which are in a mutually orthogonal relationship with one another. The apparatus includes a transmitter which previously inserts a group of predetermined synchronization symbols into an OFDM modulated transmission signal every fixed period and a receiver which demodulates a received OFDM modulated transmission signal to a baseband OFDM signal. In the receiver, an absolute value of an A/D converted digital signal is taken and the signal is bandwidth-limited to a predetermined band width. Then, it is decided whether an amplitude of the signal is larger than or smaller than a predetermined value and a decision result thereof is produced. A null section in the synchronization symbol group is detected on the basis of the decision result and a start point of another synchronization symbol subsequent to the null section is further detected. The time when both of the presence of the null section and the start point of another synchronization symbol are detected is regarded as a synchronization timing and the operation timing of a demodulator for the receiver is set to the synchronization timing.
摘要翻译： 正交频分复用调制系统的数据发送装置，其中使用彼此相互正交的多个载波来发送数据。 该装置包括一个发送器，其先前将一组预定的同步符号插入每个固定周期的OFDM调制的传输信号，以及一个接收机，将接收的OFDM调制的传输信号解调为基带OFDM信号。 在接收机中，采用A / D转换的数字信号的绝对值，并将信号带宽限制在预定的带宽。 然后，确定信号的幅度是否大于或小于预定值，并且产生其判定结果。 基于判定结果来检测同步符号组中的零部分，并进一步检测到零部分之后的另一个同步符号的起始点。 检测到零段的存在和另一个同步符号的起始点的时间被认为是同步定时，并且用于接收机的解调器的操作定时被设置为同步定时。
-
9.发明授权Synchronization detection method for data transmission apparatus and data transmission apparatus using the same 有权数据发送装置的同步检测方法及使用其的数据发送装置公开(公告)号：US06246735B1
公开(公告)日：2001-06-12
申请号：US09203564
申请日：1998-12-02
IPC分类号： H04L706
CPC分类号： H04L27/2656 , H04L7/041 , H04L27/2613
摘要： A data transmission apparatus using a digital modulation system wherein a transmitting side inserts a group of predetermined synchronization symbols into a transmission signal at predetermined intervals to be transmitted. A receiving side calculates an electric power value of a received transmission signal. When a no-signal period (null section) in the synchronization symbol group is to be detected and decided from a magnitude of the received signal electric power value, a threshold for reference of decision for detecting the null section is calculated on the basis of an average electric power value for a predetermined period in the received signal electric power value and the threshold calculated in accordance with the received signal level of the transmission signal is used to detect synchronization stably.
摘要翻译： 一种使用数字调制系统的数据发送装置，其中发送侧以预定间隔将一组预定同步符号插入到发送信号中以被发送。 接收侧计算接收的发送信号的电功率值。 当从接收信号电功率值的大小检测并确定同步符号组中的无信号周期（空区间）时，基于 使用接收信号电功率值中规定期间的平均电功率值和根据发送信号的接收信号电平计算出的阈值来稳定地检测同步。
-
10.发明授权公开(公告)号：US07016298B2
公开(公告)日：2006-03-21
申请号：US09884026
申请日：2001-06-20
IPC分类号： H04J11/00
CPC分类号： H04L5/0048 , H04L25/0226 , H04L25/0232 , H04L27/0008 , H04L27/2071 , H04L27/2602 , H04L27/2627 , H04L27/3455
摘要： A transmission apparatus of orthogonal frequency division multiplexing for multiplexing a plurality of carriers orthogonal to one another to transmit a modulated signal. The transmission apparatus includes a first modulator for outputting a code modulated in accordance a modulation scheme which can be applied with a synchronous detection for demodulation, a second modulator for outputting a code modulated in accordance with a modulation scheme different from the modulation scheme associated with the first modulator, and a distributing circuit for distributing the codes modulated by the first and second modulators to a plurality of carriers. The distributing circuit distributes the code modulated by the second modulator to all or some of carriers existing within a predetermined number of columns from at least one of both end regions of a signal transmission frequency band, and the code modulated by the first modulator to the remaining carriers.
摘要翻译： 一种正交频分复用的发送装置，用于将彼此正交的多个载波复用以发送调制信号。 发送装置包括：第一调制器，用于输出根据可以应用于解调的同步检测的调制方式调制的码;第二调制器，用于输出根据与调制方案不同的调制方案调制的码; 第一调制器和用于将由第一和第二调制器调制的代码分配给多个载波的分配电路。 分配电路将由第二调制器调制的代码分配给来自信号传输频带的两个端部区域中的至少一个的预定数量的列中存在的所有或一些载波，并且将由第一调制器调制的代码分配给剩余的 承运人
-
-
-
-
-
-
-
-
-
搜索结果
63 条记录 (耗时 0.024 秒)
