Simultaneous spatial and frequency-domain filtering at the antenna inputs achieving up to +10dBm out-of-band/beam P1dB
Simultaneous spatial and frequency-domain filtering at the antenna inputs achieving up to +10dBm out-of-band/beam P1dB
复制标题
在天线输入端同时进行空间和频域滤波，实现高达 10dBm 的带外/波束 P1dB
DOI：
10.1109/isscc.2013.6487647
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
B. Nauta
中科院分区：
文献类型：
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作者：
A. Ghaffari;E. Klumperink;F. V. Vliet;B. Nauta
具有波束成形的多天线收发器最近在低GHz频率（<6GHz）方面引起了关注[1 - 4]。在天线波束中，来自多个天线的（相移）信号相长叠加，提高了信噪比（SNR），而波束外的信号则相消叠加（即空间滤波）。通常，求和点位于一些增益模块之后，这些增益模块需要能够处理强信号。为了提高输入参考1dB压缩点（P1dB），文献[4]中提出了一种全无源开关电容方法，其提供的P1dB = +2dBm，但噪声代价较高：噪声系数（NF）= 18dB。在此，我们建议在无源混频器优先的开关RC下变频器的基带电容处直接求和。我们表明，这可以在较低噪声和较高P1dB的情况下，实现与射频带通频率滤波一起的方向相关的射频阻抗（空间滤波）。
Multi-antenna transceivers with beam-forming are recently gaining interest for low GHz frequencies (<;6GHz) [1-4]. In the antenna beam, (phase-shifted) signals from multiple antennas add constructively, improving SNR, while out-of-beam signals add destructively (i.e. spatial filtering). Usually the summation point is behind some gain blocks, which then need to be capable of handling strong signals. To improve the input-referred compression point P1dB, a fully passive switched-capacitor approach was presented in [4], providing P1dB=+2dBm, but at a high noise penalty: NF=18dB. Here we propose to sum immediately at the baseband capacitors of passive mixer-first switched-RC downconverters. We show that this can render a direction-dependent RF impedance (spatial filtering) together with RF bandpass frequency filtering at lower noise and higher P1dB.