Pre-equalization for the up-link of TDD OFDM systems
Pre-equalization for the up-link of TDD OFDM systems
复制标题
TDD OFDM系统上行链路的预均衡
DOI：
10.1109/pimrc.2001.965269
复制
发表时间：
2001
期刊：
影响因子：
--
通讯作者：
L. Ligthart
中科院分区：
文献类型：
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作者：
K. Witrisal;Yong;R. Prasad;L. Ligthart
本文研究了在时分双工 (TDD) OFDM 系统上行链路上使用预均衡的可能性。建议应用这一原理，通过省略上行链路上训练序列的使用来提高频谱效率。这是为了能够有效传输非常短的数据包（如单个 ATM 信元）而需要的。所提出的原理还使许多用户接入的基站的同步复杂度保持在较低水平。我们描述了一种限制上行链路传输功率的简单方案。通过删除因衰落而严重衰减的子载波来保持功率恒定。解释和评估了在基站检索数据的参数估计步骤。这些包括定时偏移、载波相位偏移和接收幅度的估计。考虑相干解调。
This paper investigates the possibility of using pre-equalization on the up-link of a time division duplex (TDD) OFDM system. The application of this principle is suggested to enhance the spectral efficiency by omitting the usage of training sequences on the up-link. This is desired in order to enable the efficient transmission of very short data packets, like single ATM cells. The principle proposed also keeps the complexity of synchronization low at the base station, which is accessed by many users. We describe a simple scheme to limit the transmission power on the up-link. The power is kept constant by deleting subcarriers that are severely attenuated due to fading. Parameter estimation steps for retrieving the data at the base-station are explained and evaluated. Those include the estimation of the timing-offset, the carrier phase offset, and the received magnitude. Coherent demodulation is considered.