Frequencies above 52.6 GHz have a great potential for various services. For example, the frequency range from 57-71 GHz can be used for unlicensed wireless communication and intelligent transportation system (ITS) applications. Moreover, interest has been expressed to use the frequency range from 57-71 GHz for integrated access and backhaul for New Radio (NR). In order to enable NR systems for operation above 52.6 GHz, further optimization is required.
Power efficient waveform
Power amplifier (PA) efficiency degrades at frequencies above 52.6 GHz. Thus, a new waveform to enhance PA efficiency considering the tradeoff between complexity and performance should be introduced. The new waveform should provide low peak to average power ratio (PAPR) and allow low PA backoff to enhance PA efficiency. Additionally, optimizations of channels and signals are required based on the new waveform.
Enhanced beam management
Frequencies above 52.6 GHz experience more severe propagation loss, but the higher frequencies enable larger antenna arrays. Narrow and massive beams by larger antenna arrays will bring a need for evolved techniques for beam related operations in NR.
In frequencies above 52.6 GHz, it is necessary to support larger bandwidths. In order to support larger bandwidths, there are many challenges such as increased power consumption and hardware complexity. In such case, support of narrow transmission bandwidths potentially relaxes the challenges in frequencies above 52.6 GHz.