公开(公告)号：US07430193B2

公开(公告)日：2008-09-30

申请号：US10536593

申请日：2002-11-29

申请人： Kwang-Soon Kim ,  Kyung-Hi Chang ,  Yong-Soo Cho ,  Tae-Gon Kim

发明人： Kwang-Soon Kim ,  Kyung-Hi Chang ,  Yong-Soo Cho ,  Tae-Gon Kim

IPC分类号： H04B7/00 ,  H04B7/216 ,  H04B7/212 ,  H04Q7/00 ,  H04Q7/24 ,  H04J3/00 ,  H04J1/00 ,  H04J3/06

CPC分类号： H04L27/2656 ,  H04L5/0023 ,  H04L5/0048 ,  H04L5/0053 ,  H04L27/2613 ,  H04L27/2657 ,  H04L27/2662 ,  H04L27/2678

摘要： In an OFDMA-based cellular system, a frame of a downlink signal includes a common slot and traffic slots. The common slot includes a synchronization preamble and a cell search preamble. The synchronization preamble has a structure for synchronizing time and frequency, and the cell search preamble has a cell search structure. The traffic slot includes pilot symbols provided on the time and frequency axes. A cyclic prefix is used to estimate initial symbol synchronization, and the initial symbol synchronization and the synchronization preamble are used to synchronize the frame. The synchronization frame and the cell search preamble are used to estimate time and frequency synchronization. The cell search preamble is used to search cells. When the initial synchronization is performed, the cyclic prefix is used to track the frequency, the synchronization preamble is used to track symbol synchronization, and the cell search preamble is used to track fine frequency synchronization.

摘要翻译： 在基于OFDMA的蜂窝系统中，下行链路信号的帧包括公共时隙和业务时隙。 公共时隙包括同步前导码和小区搜索前同步码。 同步前导码具有用于同步时间和频率的结构，并且小区搜索前导码具有小区搜索结构。 业务插槽包括在时间轴和频率轴上提供的导频符号。 使用循环前缀来估计初始符号同步，并且使用初始符号同步和同步前导码来同步该帧。 同步帧和小区搜索前导码用于估计时间和频率同步。 小区搜索前导码用于搜索小区。 当执行初始同步时，使用循环前缀来跟踪频率，同步前同步码用于跟踪符号同步，并且使用小区搜索前导码来跟踪精细频率同步。

公开(公告)号：US20080187065A1

公开(公告)日：2008-08-07

申请号：US11679569

申请日：2007-02-27

申请人： Kyung Hi Chang ,  Manar Mohaisen

发明人： Kyung Hi Chang ,  Manar Mohaisen

IPC分类号： H04B7/02

CPC分类号： H04W52/42 ,  H04J11/003 ,  H04J11/0033 ,  H04J11/0066 ,  H04L25/022 ,  H04L25/0228 ,  H04W52/08 ,  H04W52/241

摘要： In this patent, we propose an efficient CCI cancellation algorithm capable of working in cellular OFDM systems in high interference environments especially for users at the cell edges. We propose modified BSs' transmitters (Txs) and MS receiver (Rx) structures. Adjacent BSs use different transmitting interleaving patterns. This leads to orthogonality in the frequency domain. Furthermore, the energy of every symbol is spread over two different subcarriers to get frequency diversity. At the MS Rx, the maximum likelihood estimator MLE CCI canceller is applied to cancel signals of interfering BSs using the same frequency band. A drawback of the MLE CCI canceller is that its performances is degraded when the received power of desired and interferer signals is nearly the same. To solve this problem, the MLE CCI canceller is assisted by a closed-loop power control (CPC) scheme. The newly proposed CPC scheme is capable of detecting and combating against the situation where the equal power is received. The present invention is easily extended to cellular networks where more than one interferer signals can be considered in the MLE CCI canceller and variable number of interleaving patterns can be applied. As a result of all the above, the invention in hands can efficiently reduces the effect the CCI in cellular OFDM networks.

摘要翻译： 在该专利中，我们提出一种能够在高干扰环境中的蜂窝OFDM系统中工作的有效的CCI消除算法，特别是对于小区边缘的用户。 我们提出修改后的BSs发射机（Tx）和MS接收机（Rx）结构。 相邻的BS使用不同的传输交织模式。 这导致频域中的正交性。 此外，每个符号的能量分布在两个不同的子载波上以获得频率分集。 在MS Rx处，应用最大似然估计器MLE CCI消除器来消除使用相同频带的干扰BS的信号。 MLE CCI消除器的缺点是当所需和干扰信号的接收功率几乎相同时，其性能下降。 为了解决这个问题，MLE CCI消除器由闭环功率控制（CPC）方案辅助。 新提出的中国共产党方案能够发现和对付同等权力的情况。 本发明容易地扩展到蜂窝网络，其中在MLE CCI消除器中可以考虑多于一个干扰信号，并且可以应用可变数目的交织模式。 作为上述的结果，本发明在手中可以有效地降低细胞OFDM网络中的CCI的影响。

公开(公告)号：US07382718B2

公开(公告)日：2008-06-03

申请号：US10334354

申请日：2002-12-31

申请人： Kyung-Hi Chang ,  Yun-Hee Kim ,  Yong-Soo Cho ,  Kyung-Won Park

发明人： Kyung-Hi Chang ,  Yun-Hee Kim ,  Yong-Soo Cho ,  Kyung-Won Park

IPC分类号： H04L5/04 ,  H04L27/00 ,  H04J11/00 ,  G06F15/00

CPC分类号： H04W52/16 ,  H04L1/0618 ,  H04L25/0204 ,  H04L27/2647 ,  H04W52/42

摘要： Disclosed is a transmitting and receiving method for reducing a time-varying channel distortion in an orthogonal frequency division multiplex (OFDM) system. In the present invention, the transmitter defines M sub-channels in one data group, mathematically analyzes a change of channel for each path causing a time-varying channel distortion in a high-speed mobile environment by approximation, calculates a weight value based on the mathematical analysis and assigns the calculated weight value to transmit data of each sub-channel. Subsequently, the receiver combines the signals of these M sub-channels and demodulates the combined signals. Accordingly, the present invention greatly reduces a distortion caused by the time-varying channel to improve a bit error rate and a channel estimation performance.

摘要翻译： 公开了一种用于减少正交频分复用（OFDM）系统中的时变信道失真的发送和接收方法。 在本发明中，发射机在一个数据组中定义M个子信道，通过近似来数学地分析导致高速移动环境中的时变信道失真的每个路径的信道变化，基于 数学分析，并分配计算的权重值以发送每个子频道的数据。 随后，接收机组合这些M个子信道的信号并解调组合的信号。 因此，本发明大大减少了由时变信道引起的失真，以提高误码率和信道估计性能。

公开(公告)号：US20080089278A1

公开(公告)日：2008-04-17

申请号：US11545723

申请日：2006-10-11

申请人： Kyung Hi Chang ,  In Suk Cha ,  Joo Heo

发明人： Kyung Hi Chang ,  In Suk Cha ,  Joo Heo

IPC分类号： H04Q7/00

CPC分类号： H04W16/10 ,  H04L1/0026 ,  H04L5/0037 ,  H04L5/0044 ,  H04L5/006 ,  H04L5/0064 ,  H04W28/18 ,  H04W52/146 ,  H04W52/262 ,  H04W52/283 ,  H04W52/346 ,  H04W72/0413 ,  H04W72/0453

摘要： Provided are a dynamic channel/power allocation method for an FRP-based OFDMA system and a frame/slot structure capable of supporting the dynamic channel/power allocation method. In the FRP-based OFDMA system, each of cells has an inner cell, an outer cell and a plurality of sectors and performs data communication with a plurality of MSs therein through one or more orthogonal subchannel groups. In the dynamic channel/power allocation method, a BS receives a feedback channel condition from an MS provided with a service of the BS and allocates a subchannel group with a high SINR to each MS in consideration of the fairness and the distance information of each MS. Power is allocated to each MS on the basis of the conditions of a channel allocated to each MS, thereby obtaining a multi-user diversity gain.

摘要翻译： 提供了一种用于基于FRP的OFDMA系统的动态信道/功率分配方法和能够支持动态信道/功率分配方法的帧/时隙结构。 在基于FRP的OFDMA系统中，每个小区具有内部小区，外部小区和多个扇区，并通过一个或多个正交子信道组与其中的多个MS执行数据通信。 在动态信道/功率分配方法中，BS考虑到每个MS的公平性和距离信息，从提供有BS业务的MS接收到反馈信道条件，并向每个MS分配具有高SINR的子信道组 。 基于分配给每个MS的信道的条件，将功率分配给每个MS，从而获得多用户分集增益。

公开(公告)号：US20070237069A1

公开(公告)日：2007-10-11

申请号：US11674063

申请日：2007-02-12

申请人： Kyung Hi Chang ,  Joo Heo

发明人： Kyung Hi Chang ,  Joo Heo

IPC分类号： H04J11/00

CPC分类号： H04L25/022 ,  H04L1/0003 ,  H04L1/0019 ,  H04L1/0026 ,  H04L1/0036 ,  H04L27/2601 ,  H04W24/00 ,  H04W74/04

摘要： Provided are a multi-step channel prediction apparatus and method for adaptive transmission in an OFDM/FDD system. A channel prediction is preformed considering a time-varying characteristic of a channel changing within one slot, in addition to feedback and processing delay time between a transmitter and a receiver, and an adaptive transmission is performed. Therefore, a target PER performance can be maintained without degradation of the system performance. The channel prediction apparatus includes: a primary channel prediction unit for predicting a channel to be generated before an Lth OFDM symbol from an output of a channel estimation unit; a secondary channel prediction unit for predicting a channel to be generated before a 2Lth OFDM symbol, based on a channel value predicted by the primary channel prediction unit and a measured channel value that is a reception channel value previously checked by a mobile station; and a channel information determination unit for determining if a channel characteristic during one slot period is monotone decreasing or monotone increasing, based on the outputs of the primary channel prediction unit and the secondary channel prediction unit, and transmitting corresponding channel status information (CSI) to the transmitter. By predicting the channel considering the channel time-varying characteristic and performing the adaptive transmission, a target QoS can be maintained in the case where the mobility is about 30 km/h, without loss of the system throughput performance.

摘要翻译： 提供了一种用于OFDM / FDD系统中的自适应传输的多步信道预测装置和方法。 除了在发射机和接收机之间的反馈和处理延迟时间之外，考虑到在一个时隙内改变的信道的时变特性，执行信道预测，并且执行自适应传输。 因此，可以维持目标PER性能，而不会降低系统性能。 信道预测装置包括：主信道预测单元，用于从信道估计单元的输出预测在第L个OFDM符号之前要产生的信道; 第二信道预测单元，用于基于由主信道预测单元预测的信道值和作为先前接收信道值的测量信道值来预测在第2LOFDM符号之前要生成的信道 由移动台检查; 以及信道信息确定单元，用于基于所述主信道预测单元和所述辅助信道预测单元的输出，确定在一个时隙周期期间的信道特性是单调递减还是单调增加，以及将相应的信道状态信息（CSI）发送到 发射机。 通过考虑信道时变特性并执行自适应传输来预测信道，在移动性为约30km / h的情况下，可以保持目标QoS，而不损失系统吞吐量性能。

公开(公告)号：US07260161B2

公开(公告)日：2007-08-21

申请号：US10665085

申请日：2003-09-17

申请人： Sang-Hyun Lee ,  Soo-Jung Jung ,  Kyung-Hi Chang

发明人： Sang-Hyun Lee ,  Soo-Jung Jung ,  Kyung-Hi Chang

IPC分类号： H03D1/04

CPC分类号： H04B1/71072 ,  H04B1/71075

摘要： Disclosed is a hybrid multi-user interference cancellation method for canceling interference between a plurality of user signals, which comprises: receiving a plurality of external user signals, calculating powers of the user signals, and numbering the calculated signal powers in their intensity orders; sorting the user numbers in descending order; forming at least one user cluster so that the signal powers following the sorted user numbers may differ less from a central value or a mean value in the same cluster; and performing parallel interference cancellation on the respective user signals within the same cluster, and performing successive interference cancellation between the formed clusters.

摘要翻译： 公开了一种用于消除多个用户信号之间的干扰的混合多用户干扰消除方法，包括：接收多个外部用户信号，计算用户信号的功率，并以其强度次序对所计算的信号功率进行编号; 按降序对用户编号进行排序; 形成至少一个用户群集，使得跟随排序的用户号码的信号功率可以与相同群集中的中心值或平均值不同; 并对同一簇内的各个用户信号执行并行干扰消除，并且在形成的簇之间执行连续的干扰消除。

公开(公告)号：US07126925B2

公开(公告)日：2006-10-24

申请号：US10184107

申请日：2002-06-28

申请人： Dae-Ho Kim ,  Chang-Wahn Yu ,  Kyung-Hi Chang

发明人： Dae-Ho Kim ,  Chang-Wahn Yu ,  Kyung-Hi Chang

IPC分类号： H04B7/216

CPC分类号： H04B1/7113 ,  H04B1/7117 ,  H04B2201/70707

摘要： An apparatus for multi-path search using a dual code generator includes: first and second code generators for generating first and second search codes, changing phases, and generating a search-done interrupt; a multi-path search engine for receiving the search codes from the code generators and performing a search process for detection of the multiple paths; a search controller for controlling the code generators to generate the search codes, and sending the search-done interrupt from the code generators; and a drive controller for generating a slewing command to the search paths and a search command, sending the commands to the search controller, reading search results from the search controller upon generation of the search-done interrupt, and generating second slewing and search commands for a new search process.

公开(公告)号：USRE39275E1

公开(公告)日：2006-09-12

申请号：US10463878

申请日：2003-06-18

申请人： Kyung Hi Chang ,  Hyung Rae Park ,  Mun Geon Kyeong ,  Eung Soon Shin ,  Yang Gi Kang ,  Youn Ok Park

发明人： Kyung Hi Chang ,  Hyung Rae Park ,  Mun Geon Kyeong ,  Eung Soon Shin ,  Yang Gi Kang ,  Youn Ok Park

IPC分类号： G01S3/16 ,  G01S3/28 ,  H04B1/69 ,  H04B1/10 ,  H04B7/10 ,  H01Q3/26 ,  H04L1/02

CPC分类号： H04B1/7115 ,  H01Q3/2605 ,  H04B1/709 ,  H04B7/086

摘要： In the hardware-efficient demodulator for a CDMA adaptive antenna array mechanism of a mobile radio communication system, a correlators bank receives digital baseband signals received through an antenna array of a base station and computes correlation values with a local code sequence. A beamformer receives the digital baseband signals and the correlation values from the correlators bank and calculates beamforming weight vectors. A searchers bank receives the digital baseband signals and calculates an initial acquisition and reliable timing information for a multipath search by a common work with the beamformer, which uses a beamforming algorithm. A beamforming complex multiplier for a finger performs a complex multiplication for the beamforming weight vectors and the digital baseband signals, and sums up them. A finger bank receives output signals from the beamforming complex multiplier, executes a code tracking for an alignment between a transmission code and a phase by each multipath on the basis of the multipath search timing information to then provide the timing information of the multipath tracking to the correlators bank, and outputs signals of dispreaded multipath through a time alignment based on each path. A multipath combiner performs a multipath combination for the output signals of the finger bank on a time base and outputting it.

摘要翻译： 在用于移动无线电通信系统的CDMA自适应天线阵列机构的硬件高效解调器中，相关器组接收通过基站的天线阵列接收的数字基带信号，并用本地码序列计算相关值。 波束形成器从相关器组接收数字基带信号和相关值，并计算波束成形权重向量。 搜索库接收数字基带信号，并且通过使用波束形成算法的波束形成器通过共同的工作来计算用于多路径搜索的初始捕获和可靠的定时信息。 用于手指的波束形成复数乘法器对于波束成形加权矢量和数字基带信号执行复数乘法，并将它们相加。 手指组从波束形成复数乘法器接收输出信号，根据多路径搜索定时信息对每个多路径执行用于发送码和相位之间的对齐的码跟踪，然后将多径跟踪的定时信息提供给 相关器组，并且基于每个路径通过时间对齐来输出分布的多路径的信号。 多路径组合器在时基上为手指组的输出信号执行多路径组合并输出。

公开(公告)号：US07093189B2

公开(公告)日：2006-08-15

申请号：US10334352

申请日：2002-12-31

申请人： Sang-Hyun Lee ,  Kwang-Soon Kim ,  Kyung-Hi Chang

发明人： Sang-Hyun Lee ,  Kwang-Soon Kim ,  Kyung-Hi Chang

IPC分类号： H03M13/00 ,  H03M13/03

CPC分类号： H03M13/136 ,  H03M13/4115 ,  H03M13/451

摘要： An RM code soft decision decoding method using decision by majority comprises: (a) performing multiplication on a bit group of a codeword, and calculating an information bit's estimate group; (b) summating elements of the group and obtaining a final estimate of the degree's information bit to perform decision by majority; (c) using the final estimate to generate a codeword corresponding to each degree's information bit final estimate, and removing the generated codeword from the codeword of (a); (d) repeating the step (c) for the final estimates of the remaining degrees' information bits other than zero-order information bit; and (e) summating elements of codewords of results performed on the final estimates of the first-order information bit in (d) to estimate the zero-order information bit's final estimate.

摘要翻译： 使用多数决定的RM码软判决解码方法包括：（a）对码字的比特组执行乘法，并计算信息比特的估计组; （b）总结该小组的要素，并获得学位信息的最终估计数据，以便按多数确定; （c）使用最终估计来生成与每个度的信息比特最终估计相对应的码字，以及从（a）的码字去除所生成的码字; （d）重复步骤（c）以获得零级信息比特以外的其余度数信息比特的最终估计值; 和（e）对（d）中的一阶信息位的最终估计执行的结果的码字的元素求和，以估计零阶信息比特的最终估计。

公开(公告)号：US20060114812A1

公开(公告)日：2006-06-01

申请号：US10536593

申请日：2002-11-29

申请人： Kwang-Soon Kim ,  Kyung-Hi Chang ,  Yong-Soo Cho ,  Tae-Gon Kim

发明人： Kwang-Soon Kim ,  Kyung-Hi Chang ,  Yong-Soo Cho ,  Tae-Gon Kim

IPC分类号： H04J11/00

CPC分类号： H04L27/2656 ,  H04L5/0023 ,  H04L5/0048 ,  H04L5/0053 ,  H04L27/2613 ,  H04L27/2657 ,  H04L27/2662 ,  H04L27/2678

摘要： In an OFDMA-based cellular system, a frame of a downlink signal includes a common slot and traffic slots. The common slot includes a synchronization preamble and a cell search preamble. The synchronization preamble has a structure for synchronizing time and frequency, and the cell search preamble has a cell search structure. The traffic slot includes pilot symbols provided on the time and frequency axes. A cyclic prefix is used to estimate initial symbol synchronization, and the initial symbol synchronization and the synchronization preamble are used to synchronize the frame. The synchronization frame and the cell search preamble are used to estimate time and frequency synchronization. The cell search preamble is used to search cells. When the initial synchronization is performed, the cyclic prefix is used to track the frequency, the synchronization preamble is used to track symbol synchronization, and the cell search preamble is used to track fine frequency synchronization.

摘要翻译： 在基于OFDMA的蜂窝系统中，下行链路信号的帧包括公共时隙和业务时隙。 公共时隙包括同步前导码和小区搜索前同步码。 同步前导码具有用于同步时间和频率的结构，并且小区搜索前导码具有小区搜索结构。 业务插槽包括在时间轴和频率轴上提供的导频符号。 使用循环前缀来估计初始符号同步，并且使用初始符号同步和同步前导码来同步该帧。 同步帧和小区搜索前导码用于估计时间和频率同步。 小区搜索前导码用于搜索小区。 当执行初始同步时，使用循环前缀来跟踪频率，同步前同步码用于跟踪符号同步，并且使用小区搜索前导码来跟踪精细频率同步。