Name: Aluminum CNC machining prototype of 5G AAU module
Color: natural color
Surface treatment: deburring
Accuracy: +-0.02mm
Material: aluminum alloy
Processing cycle: 3-7 working days
Testing standard: 2D drawing file provided by the customer

Large-scale multiple input multiple output technology is one of the core technologies of 5G. Using multi-antenna space division multiplexing to double the spectrum efficiency, enhance network coverage and system capacity. Massive MIMO uses more than 100 antennas, which is an order of magnitude higher than that of traditional base stations. Therefore, more independent data streams can be transmitted between the system and the terminal, thereby exponentially improving spectrum efficiency and energy efficiency. The increase in the number of antennas directly leads to the difference in signal processing methods, causing new problems and challenges.

The Massive MIMO base station in the prior art generally adopts an all-digital architecture solution. Take 16-channel Massive MIMO base station as an example. The active antenna unit (AAU) is composed of a radio remote unit (RRU) and a passive antenna. The device architecture of the AUU supporting the antenna remote electronic adjustment function is shown in Figure 1.

Among them, an antenna has a total of 12 elements in the vertical direction. The 16 radio frequency channels are connected with the digital intermediate frequency, and the calibration network and the phase shift network are connected between the 16 radio frequency channels and the 16 wireless channels. In each radio frequency channel, a digital to analog converter (DAC) is connected to the transmitting channel. The transmitting channel is connected with a power amplifier (Power Amplifiers, PA), and an analog-to-digital converter (Analog to Digital Converter, ADC) is connected with the receiving channel. The receiving channel is connected to a low noise amplifier (Low Noise Amplifiers, LNA), the PA and LNA are connected to the antenna multiplexing unit, and the antenna multiplexing unit is connected to the filter.

However, in the prior art AUU device architecture, the feeder from the power amplifier to the antenna channel is longer, the loss is greater, and the insertion loss of the phase shift network is greater.