Base Station Diversity Propagation Measurements at 73 GHz Millimeter-Wave for 5G Coordinated Multipoint (CoMP) Analysis

TL;DR

This study presents extensive 73 GHz millimeter-wave measurements in an urban environment to analyze base station diversity and CoMP, revealing significant coverage improvements and insights into interference for future 5G small-cell deployments.

Contribution

It provides large-scale directional measurements and models at 73 GHz, demonstrating the benefits of macro-diversity and CoMP in urban mmWave 5G networks.

Findings

Coverage improves with multiple base stations and beamforming.

Directional path loss models match existing literature.

Cell outage probabilities decrease with increased base station cooperation.

Abstract

This paper describes wideband (1 GHz) base station diversity and coordinated multipoint (CoMP)-style large-scale measurements at 73 GHz in an urban microcell open square scenario in downtown Brooklyn, New York on the NYU campus. The measurements consisted of ten random receiver locations at pedestrian level (1.4 meters) and ten random transmitter locations at lamppost level (4.0 meters) that provided 36 individual transmitter-receiver (TX-RX) combinations. For each of the 36 radio links, extensive directional measurements were made to give insights into small-cell base station diversity at millimeter-wave (mmWave) bands. High-gain steerable horn antennas with 7-degree and 15-degree half-power beamwidths (HPBW) were used at the transmitter (TX) and receiver (RX), respectively. For each TX-RX combination, the TX antenna was scanned over a 120-degree sector and the RX antenna was scanned over the entire azimuth plane at the strongest RX elevation plane and two other elevation planes on both sides of the strongest elevation angle, separated by the 15-degree HPBW. Directional and omnidirectional path loss models were derived and match well with the literature. Signal reception probabilities derived from the measurements for one to five base stations that served a single RX location show significant coverage improvement over all potential beamformed RX antenna pointing angles. CDFs for nearest neighbor and Best-N omnidirectional path loss and cell outage probabilities for directional antennas provide insights into coverage and interference for future mmWave small-cells that will exploit macro-diversity and CoMP.