Features of Base Station
The base station was designed from scratch and is designed to be a state of the art 5G system. In particular some of the highlights of the 5G base station being developed are as follows
- Modular architecture: The entire 5G base station is designed to be modular in nature. The hardware and software follow this principle and this allows most of the modules to be re-used for different configurations. For example, the hardware can be used (re) to build 16 antenna, 32 antenna and 64 antenna systems. The operating frequency can also be changed easily by re-designing very few modules.
- Massive MIMO support: Massive MIMO is a key technology that distinguishes 5G from 4G and is responsible for the fast speeds that 5G promises. 5G can support very large panels of antennas leading to multi-stream transmission. The 5G testbed supports till 64 antennas in the sub 6GHz range and till 256 antenna in the mmWave band. Realising massive MIMO systems require special pilots introduced in 5G standard.
- Large bandwidth: One of the salient features of 5G is the large bandwidth, about 100 MHz in FR1 and 400 MHz in FR2. The testbed hardware is designed to support these large bandwidths
- mmWave support: The testbed supports mmWave RF at 26 GHz and 28 GHz. In addition, beamforming using phased array is supported in these frequencies
- Interoperability support. The 5G base station is designed so that the different modules can be interoperate with other vendors. For example, ORAN is a new protocol that leads to inter-operability between various base stations and in particular defines the e-CPRI standard for the fronthaul. This has been implemented in the base station designed in the project. Similarly, FAPI protocol has been implemented for the L1 and L2/L3 connectivity. So inter-operability testing with various vendors (following these standards) will be easy.