The fifth-generation (5G) system utilizing millimeter wave is available in Japan, but more bandwidth is demanded by the mobile phone operators to accommodate the demand for high data rate.Allocation of viqua-f4 the vacant spectrum is impossible due to the past spectrum allocation to other radio systems.For example, 24.25-27.
5 GHz has been allocated for the fixed wireless access (FWA) and license exempt small power data communication system in Japan.Although Japanese government is considering to license a part of the band for 5G under the spectrum sharing scheme, the coexistence design is quite challenging due to unavailable operation data of such systems in a form of database for the coexistence study.For this purpose, this paper introduces a maximum-likelihood estimator (MLE), which utilizes the angle-of-arrival (AoA) and received power of the line-of-sight (LOS)/diffraction paths as well as the map database to simultaneously estimate these unknown parameters via the spectrum sensing.It was applied to the measurement data obtained from a sub-urban environment where a commercial fixed wireless access system with similar operational parameters is under operation.
Its performance was evaluated for a different number of receiver (Rx) points.The results showed that the parameter estimation accuracy is proportional to the number of receiver points.The distance and orientation errors of 45 m and 5 deg were achieved at 90th percentile with 40 Rx points.Furthermore, the prediction performance of the effective isotropic radiated power (EIRP) was decent, albeit a 888392593481 slight underestimation of the beamwidth.