Effective Indoor Coverage via Radio-Over-Cable Fronthauls: Analog Fronthauls Come of Age

This article considers a radio-over-cable (RoC)based analog link on a local area network (LAN) cable [e.g., category (CAT) 5] as the last hop of the fronthaul for indoor mobile service coverage. We first present state-of-the-art mobile systems with RoC-based fronthauls and then discuss a number of critical issues regarding real implementation. These issues include the function module, called the radio-cable access unit (RCU), that interfaces with the radio frequency (RF) and intermediate frequency (IF) signals along the LAN cable as well as the design of an RF front end (RF-FE) that supports time-division duplex (TDD) and frequency-division duplex (FDD) modes. Then, the proposed nonconfigurable distributed antenna unit (NC-DAU) and corresponding resource-mapping scheme [NC air-tocable (NC-A2C)] are introduced, aiming to achieve lowcost, large-scale indoor deployment. We examine the performance of the NC-A2C and compare it with the optimal case.