中文说明：IN 最近几年，直接转换接收器已绘制了很多关注由于其低功耗和低成本的执行。然而一些直接转换接收机中的不匹配可能会严重降低系统性能，如在阶段和正交相位 (我 / Q) 的不平衡和载波频率偏移量 (CFO)。我 Q 的不平衡，是由于不匹配之间的我的振幅和相位和 Q 处的本地振荡器而 CFO 是由于载波频率在发射器和接收器的不匹配。它已知的 I / Q 失衡和首席财务官可以导致严重的载波间干扰 (ICI) 在正交频分复用 (OFDM) 系统。其结果是，误码率 (BER) 有错误-地板。在假定信道频率响应是光滑的频率域估计方法已提议联合估计的 I / Q 失衡和信道的频率响应。最近，利用 DFT 矩阵的大小是通常大于信道长度 OFDM 系统中的事实，时间域提出一个方法是联合估计的我 / Q 和通道的反应。频率域和时间域的方法只需要其中一个 OFDM 块为培训和可以实现良好的性能。首席财务官的估计，一种低复杂度最大似然 (毫升) 技术，拟。首席财务官和我的联合估计 / Q 失衡调查
English Description：
IN recent years, direct conversion receiver has drawn a lot of attention due to its low power consumption and low implementation cost. However some mismatches in direct conversion receiver can seriously degrade the system performance, such as in-phase and quadrature-phase (I/Q) imbalance and carrier frequency offset (CFO). The I/Q imbalance is due to the amplitude and phase mismatches between the I and Q-branch of the local oscillator whereas the CFO is due to the mismatch of carrier frequency at the transmitter and receiver. It is known that the I/Q imbalance and CFO can cause a serious inter-carrier interference (ICI) in orthogonal frequency division multiplexing (OFDM) systems. As a result, the bit error rate (BER) has an error-flooring. In assuming that the channel frequency response is smooth, a frequency-domain estimation method h