How Much Spectrum is Too Much in Millimeter Wave Wireless Access

Great increase in wireless access rates might be attainable using the large amount of spectrum available in the millimeter wave (mmWave) band.However, higher propagation losses inherent in these frequencies must be addressed, especially at ranges beyond 100 meters and in non-line-of-sight settings. Otherwise, using wider channels in noise limited settings may be ineffective or even counterproductive when accounting for channel estimation penalty. Therefore, the Equivalent Isotropic Radiated Power (EIRP) is a key parameter. We find that, with 11 dBi antenna gain at the receiver, at 52 dBm EIRP the maximum beneficial bandwidth at 28/60 GHz is less than 1 GHz at a distance beyond 210/120 meters (with maximum throughput about 200 Mbps) and less than 100 MHz beyond 400/230 meters (with maximum throughput about 20 Mbps). At a EIRP of 85 dBm, corresponding to the FCC limit of 75 dBm per 100 MHz, 1 Gbps rate can be delivered using 1 GHz bandwidth up to 860/500 meters.