A Multi-channel Broadband Low-noise Amplifier

In this paper, a 4-channel low noise broadband amplifier operating at $3.5-4.5 \mathrm{GHz}$ is designed for massive MIMO(Multiple-Input Multiple-Output) mobile communication system. It has the advantage of low noise, large gain, good consistency and small volume. The real test results show that in the operating frequency band of $3.5-4.5 \mathrm{GHz}$, the average noise figure of the four channels of the low noise amplifier is 2.08 dB, the average gain is $\mathbf{1 2. 4 8} \mathbf{~ d B}$, the gain flatness is about $\pm 1.39 \mathrm{~dB}$, and both the input and output reflection coefficients are less than -10 dB. The amplifier operates at a supply voltage of 5 V and has a single-channel power consumption of 350 mW. The physical circuit board size is $\mathbf{4 8} \mathbf{~ m m} \times 72 \mathrm{~mm} \times 0.95 \mathrm{~mm}$.