Suburban Fixed Wireless Access Channel Measurements and Models at 28 GHz for 90% Outdoor Coverage

Fixed wireless access at mm/cm bands has been proposed for high-speed broadband access to suburban residential customers. Achieving adequate coverage with high gain antennas is key to realizing the full promise of the wide bandwidth available. We report extensive outdoor measurements at 28 GHz in suburban residential areas in New Jersey and Chile, with over 1700 links measured for 6 NJ houses and 5 Chilean houses with and without line-of-sight (LOS) using a specialized narrowband channel sounder, at ranges reaching 200 m. The measurements, applicable to fixed wireless access (FWA), involved a 50o (10 dBi) transmit antenna placed on the exterior of a street-facing window on the first or second floor based on accessibility. A 10o (24 dBi) receive horn antenna was mounted on top of a van mast at 3 m height, emulating a lamppost-mounted base station. The 10o base horn antenna was spun at speeds up to 300 rpm to capture azimuthal angular power distribution with 1-deg granularity. It is found that in NJ suburban environment the LOS condition even on the same street is extremely unlikely beyond 30 m. 90% of links at ranges over 30 m had excess loss of over 15 dB, implying non-line-of-sight (NLOS) conditions. Measured path gain-distance dependence is well represented by power-law models with a slope of 4, 1-m intercept of -45 dB, with log-normal deviation of 6.4 dB. Azimuth gains at the base are degraded through scattering by more than 4.3 dB for 10% of links. It was found that, with 51 dBm EIRP at the FWA base station and 11dBi antenna at CPE, 1Gbps downlink rate can be delivered to an outdoor mounted CPE for up to 100m from a base station deployed in the same street with 90% coverage guarantee. The corresponding rate will be significantly reduced if the CPE and the serving base station are in different streets.