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    Interference and noise estimation in an OFDM system
    1.
    发明授权
    Interference and noise estimation in an OFDM system 有权
    OFDM系统中的干扰和噪声估计

    公开(公告)号：US08477592B2

    公开(公告)日：2013-07-02

    申请号：US10809538

    申请日：2004-03-24

    申请人： Arak Sutivong ,  Ayman Fawzy Naguib ,  Avneesh Agrawal

    发明人： Arak Sutivong ,  Ayman Fawzy Naguib ,  Avneesh Agrawal

    IPC分类号： H04J11/00

    CPC分类号： H04L1/20 ,  H04L27/2647

    摘要： Noise and interference can be independently measured in a multiple user Orthogonal Frequency Division Multiplexing (OFDM) system. Co-channel interference is measured in a frequency hopping, multiple user, OFDM system by tracking the sub-carriers assigned to all users in a particular service area or cell. The composite noise plus interference can be determined by measuring the amount of received power in a sub-carrier whenever it is not assigned to any user in the cell. A value is stored for each sub-carrier in the system and the value of noise plus interference can be a weighted average of the present value with previously stored values. The noise component can be independently determined in a synchronous system. In the synchronous system, all users in a system may periodically be prohibited from broadcasting over a sub-carrier and the received power in the sub-carrier measured during the period having no broadcasts.

    摘要翻译： 噪声和干扰可以在多用户正交频分复用（OFDM）系统中独立测量。 通过跟踪分配给特定服务区域或小区中的所有用户的子载波，在跳频，多用户OFDM系统中测量同信道干扰。 复合噪声加干扰可以通过在子载波中没有分配给小区中的任何用户时测量子载波中的接收功率的量来确定。 为系统中的每个子载波存储一个值，并且噪声加干扰的值可以是具有先前存储的值的当前值的加权平均值。 噪声分量可以在同步系统中独立确定。 在同步系统中，系统中的所有用户可以周期地禁止通过子载波进行广播，并且在没有广播的时段期间测量的子载波中的接收功率。

    Power control and scheduling in an OFDM system
    2.
    发明授权
    Power control and scheduling in an OFDM system 有权
    OFDM系统中的功率控制和调度

    公开(公告)号：US07012912B2

    公开(公告)日：2006-03-14

    申请号：US10809605

    申请日：2004-03-24

    申请人： Ayman Fawzy Naguib ,  Avneesh Agrawal ,  Arak Sutivong

    发明人： Ayman Fawzy Naguib ,  Avneesh Agrawal ,  Arak Sutivong

    IPC分类号： H04J1/00

    CPC分类号： H04W52/24 ,  H04L5/0007 ,  H04L5/0044 ,  H04L5/0058 ,  H04L5/006

    摘要： A system and method for power control and scheduling of sub-carriers in an OFDM communication system. The receiver dynamic range can be minimized by a power control loop that attempts to maintain received power over a noise floor in a predetermined range. If the received power relative to a noise floor in allocated sub-carriers exceeds the predetermined range and the total received power is at the minimum, the scheduling system allocates an additional sub-carrier to the communication link. Additionally, if the received power relative to the noise floor is less than the predetermined range minimum, and the total received power is at a maximum, the scheduling system de-allocates a sub-carrier from the communication link. The scheduling system may also adjust an encoding rate to maintain a relatively constant symbol rate in each sub-carrier.

    摘要翻译： 一种用于OFDM通信系统中的子载波的功率控制和调度的系统和方法。 可以通过功率控制环路来最小化接收器动态范围，该功率控制环路尝试在预定范围内的噪声基底上保持接收功率。 如果所分配的子载波中相对于本底噪声的接收功率超过预定范围并且总接收功率处于最小，则调度系统向通信链路分配附加子载波。 此外，如果相对于本底噪声的接收功率小于预定范围最小值，并且总接收功率处于最大值，则调度系统从通信链路去分配子载波。 调度系统还可以调整编码速率以在每个子载波中维持相对恒定的符号率。

    Rate selection for a quasi-orthogonal communication system
    8.
    发明授权
    Rate selection for a quasi-orthogonal communication system 有权
    准正交通信系统的速率选择

    公开(公告)号：US07809336B2

    公开(公告)日：2010-10-05

    申请号：US11150417

    申请日：2005-06-10

    申请人： Ayman Fawzy Naguib ,  Alexei Gorokhov ,  Tingfang Ji ,  Dhananjay Gore ,  Arak Sutivong

    发明人： Ayman Fawzy Naguib ,  Alexei Gorokhov ,  Tingfang Ji ,  Dhananjay Gore ,  Arak Sutivong

    IPC分类号： H04B1/00 ,  H04B7/00

    CPC分类号： H04L1/0019 ,  H04L1/0003 ,  H04L1/0016 ,  H04L1/06 ,  H04L25/0212 ,  H04L25/0228 ,  H04L25/0242 ,  H04L25/0256

    摘要： To select a rate for a transmitter in a communication system, a receiver obtains a channel response estimate and a received SINR estimate for the transmitter, e.g., based on a pilot received from the transmitter. The receiver computes a hypothesized SINR for the transmitter based on the channel response estimate and the received SINR estimate. The receiver then selects a rate for the transmitter based on (1) the hypothesized SINR and (2) characterized statistics of noise and interference at the receiver for the transmitter, which may be given by a probability density function (PDF) of SINR loss with respect to the hypothesized SINR. A look-up table of rate versus hypothesized SINR may be generated a priori for the PDF of SINR loss. The receiver may then apply the hypothesized SINR for the transmitter to the look-up table, which then provides the rate for the transmitter.

    摘要翻译： 为了在通信系统中选择发射机的速率，接收机例如基于从发射机接收到的导频，获得用于发射机的信道响应估计和接收到的SINR估计。 接收机基于信道响应估计和接收的SINR估计来计算发射机的假设SINR。 接收机然后基于（1）假设的SINR和（2）用于发射机的接收机处的噪声和干扰的特征统计来选择发射机的速率，其可以由SINR丢失的概率密度函数（PDF）给出， 尊重假设的SINR。 速率与假设SINR的查找表可能会先于SINR损失的PDF生成。 然后，接收机可以将发射机的假设SINR应用于查找表，然后查找表提供发射机的速率。