公开(公告)号：US07190717B2

公开(公告)日：2007-03-13

申请号：US11233452

申请日：2005-09-22

Applicant: Channamallesh G. Hiremath ,  Udayan Dasgupta ,  Zigang Yang ,  Umashanker S. Iyer ,  Michael E. Locke

Inventor： Channamallesh G. Hiremath ,  Udayan Dasgupta ,  Zigang Yang ,  Umashanker S. Iyer ,  Michael E. Locke

IPC: H04L5/16

CPC classification number: H04L5/006 ,  H04L1/0071 ,  H04L1/04 ,  H04L5/0007 ,  H04L5/0044 ,  H04L27/2647

Abstract: A system and method for reordering tones of a DMT signal within a communication system is described. Cross tone correlated noise in a received signal is identified and rearranged such that tones with correlated noise are spread out throughout the received signal before being processed by a decoder such as, Viterbi decoder. In an embodiment, two tones with the most correlated noise are placed at each end of the sequence of tones presented to the Viterbi decoder. In some embodiment, the tones with correlated noise can be spread such that two adjacent tones with correlated noise have a minimum distance of at least three tones between them at the input to the Viterbi decoder. In other embodiment, tones in the received signal can be processed in various kinds of interleavers for reordering according to the interleaver scheme.

Abstract translation: 描述了用于在通信系统内重新排序DMT信号的音调的系统和方法。 识别和重新排列接收信号中的交叉音相关噪声，使得具有相关噪声的音调在由诸如维特比解码器之类的解码器处理之前，在整个接收信号中被扩展。 在一个实施例中，具有最相关噪声的两个音调被放置在呈现给维特比解码器的音调序列的每一端。 在一些实施例中，可以扩展具有相关噪声的音调，使得具有相关噪声的两个相邻音调在维特比解码器的输入处具有至少三个音调的最小距离。 在其他实施例中，可以根据交织器方案在各种交织器中处理接收信号中的音调以进行重新排序。

公开(公告)号：US07023929B2

公开(公告)日：2006-04-04

申请号：US10191994

申请日：2002-07-10

Applicant: Fernando A. Mujica ,  Udayan Dasgupta ,  Mangesh Sadafale ,  Sandeep Oswal ,  Prakash Easwaran

Inventor： Fernando A. Mujica ,  Udayan Dasgupta ,  Mangesh Sadafale ,  Sandeep Oswal ,  Prakash Easwaran

IPC: H04K1/10

CPC classification number: H04L27/367 ,  H04L27/2626

Abstract: A method of providing an improved transfer function for a Discrete Multitone (DMT) type modulation transmitter with digital filtering after modulation followed by digital to analog converter and analog filtering is provided by sending a test signal to said transmitter and measuring the results of the test signal to determine the transfer function. The inverse of the transfer function that needs to be compensated is determined and the inverse of transfer function to be compensated is truncated to the region of interest (H2). The desired band split component of pre-compensation filter is designed (H3). The desired target frequency response of the pre-compensation filter is determined by H4=H2*H3 where H4 is the multiplication of H2 and H3 Given the target frequency response in H4 Hermetian symmetry is imposed on the frequency response. The inverse Fourier transform (IFFT) is taken to generate a time domain filter, h5. The characteristic of this filter is added at the digital filtering after modulation.

Abstract translation: 通过向所述发射机发送测试信号并测量测试信号的结果，提供一种为调制后的数字滤波后的数模转换器和模拟滤波器为离散多音（DMT）型调制发射机提供改进的传递函数的方法 确定传递函数。 确定需要补偿的传递函数的逆，并且要补偿的传递函数的逆被截断到感兴趣的区域（H 2> 2）。 设计了预补偿滤波器的期望频带分离分量（H 3 3 3）。 预补偿滤波器的期望目标频率响应由H 4 = H 2 / H 3 3 H 3确定，其中H 4 < 假定在H 4中的目标频率响应，Hermetian对称性被施加在频率响应上，则/ SUB>是H 2 2和H 3 3的乘法。 采用逆傅里叶变换（IFFT）来产生时域滤波器h 5。 该滤波器的特性在调制后的数字滤波中相加。

公开(公告)号：US20050169358A1

公开(公告)日：2005-08-04

申请号：US11043218

申请日：2005-01-26

Applicant: Arthur Redfern ,  Udayan Dasgupta

Inventor： Arthur Redfern ,  Udayan Dasgupta

IPC: H04B1/38 ,  H04L27/26

CPC classification number: H04L27/2608 ,  H04B1/38

Abstract: An integrated circuit 18 is provided that includes a memory 32 and a memory modification component 33. The memory 32 maintains a bits count, a gain, and a tone order for each of a plurality of discrete multi-tone sub-channels. The memory modification component 33 operable to control an in-service modification of at least some of the bits count, the gain, and the tone order using a single bits, gains and tone order table.

Abstract translation: 提供了包括存储器32和存储器修改组件33的集成电路18.存储器32维持多个离散多音调子频道中的每一个的比特计数，增益和音调顺序。 存储器修改组件33可用于使用单个比特，增益和音调顺序表来控制比特计数，增益和音调顺序中的至少一些的在职修改。