Millimeter Wave Channel Modeling and Cellular Capacity Evaluation

Abstract

With the severe spectrum shortage in conventional cellular bands, millimeter wave (mmW) frequencies between 30 and 300 GHz have been attracting growing attention as a possible candidate for next-generation micro-and picocellular wireless networks. The mmW bands offer orders of magnitude greater spectrum than current cellular allocations and enable very highdimensional antenna arrays for further gains via beamforming and spatial multiplexing. This paper uses recent real-world measurements at 28 and 73 GHz in New York City to derive detailed spatial statistical models of the channels and uses these models to provide a realistic assessment of mmW micro-and picocellular networks in a dense urban deployment. Statistical models are derived for key channel parameters including the path loss, number of spatial clusters, angular dispersion and outage. It is found that, even in highly non-line-of-sight environments, strong signals can be detected 100m to 200m from potential cell sites, potentially with multiple clusters to support spatial multiplexing. Moreover, a system simulation based on the models predicts that mmW systems can offer an order of magnitude increase in capacity over current state-of-the-art 4G cellular networks with no increase in cell density from current urban deployments.

Channel Models and Beamforming at Millimeter-Wave Frequency Bands

“…For outdoor cellular scenarios, a seminal work [23] reports pathloss exponents of 3.6 and 10.4 for the intendedand outside-coverage areas at 55 GHz in urban microcellular street canyon scenarios. A number of pathloss exponents and shadowing estimates are reported [24]- [28] for a peerto-peer and cellular outdoor scenarios at various mm-wave frequencies as summaized in Table 1. Dependence of the base and mobile antenna heights on the pathloss exponent and shadowing values are reported in [29], [30].…”

“…[70] reports angular spreads of an indoor NLOS channel for different Tx and Rx antenna polarizations, showing that they vary about ±40% and ±10% around the median value on the azimuth and elevation domains, respectively. The angular spread values in outdoor cellular scenarios are presently lacking, though there have been several measurements that allow for them, e.g., [24], [28], [71].…”

“…[79] reports the standard deviation of 35 • in desktop scenarios. The works [24], [28], [60], [94] report a angularly-selective PAS in built-up urban areas at 28 and 73 GHz. In [24], [28], maximum 4 main directions of multipaths were observed at an elevated base station and a mobile, with each direction having angular spreads of about 15 • and less than 6 • in azimuth and elevation, respectively.…”

Coverage and rate analysis in the uplink of millimeter wave cellular networks with fractional power control

“…Since earlier simulation results in [6,7] reveals that mmWave networks are more likely to be noise-limited in an urban setting, we also present the noise-limited approximation of the coverage probability. For the noiselimited approximation, σ 2 z∈Z g z L(D z )G z R α 0 τ z , the signal-to-noise-ratio (SNR) coverage probability can be expressed from Theorem 1 as…”

“…Only recently did survey measurements and *Correspondence: oluwakayode.onireti@glasgow.ac.uk 1 School of Engineering, University of Glasgow, University Avenue, G12 8QQ Glasgow, UK Full list of author information is available at the end of the article capacity studies of mmWave technology reveal its promise for urban small cell deployments [1,[6][7][8]. In addition to the huge available bandwidth in the mmWave band, the smaller wavelength associated with the band allows for the use of more miniaturized antennas at the same physical area of the transmitter and receiver to provide array gain [2,6]. With such large antenna array, the mmWave cellular system can apply beamforming at the transmit and receive sides to provide array gain which compensates for the near-field pathloss [9].…”