Performance analysis with LMMSE for MIMO LTE on the High Altitude Platform Station

High Altitude Platform Station (HAPs) is a new communications infrastructure that uses air balloon to carry high data rate service and wide bandwidth. One technique to make it happen is Long Term Evolution (LTE), LTE support capacity increasing, expand coverage area, data rate increasing, low latency, multi-antenna, and can be integrated with other systems. To improve the performance of LTE in capacity building, coverage area and data rate, it can use the multi-antenna techniques both on receiver or transmitter or often called multiple input multiple output (MIMO). To ensure reliability and good performance in achieving high transmission rate, it can use coherent detection which requires knowledge of the channel for accurate channel estimation. In this study, estimation that has been used is the Linear Minimum Mean Square Error (LMMSE). Channel estimation is used to find out information about the channel condition between the transmitter and the receiver so that the performance of Bit Error Rate (BER) increase and expand the coverage area of the same BER compared without estimation. In addition, modulation level, train velocity and Signal to Noise Ratio (SNR) can also affect the amount of BER at the receiver.