In addition to the development of 2 technologies with Fujitsu Limited for silent failures detection and location in IP networks that we talked about yesterday, this comes as another step by Docomo in preparation for its extra-high-speed LTE mobile service scheduled to commence in December 2010. Docomo’s plan is to “layer a 2GHz LTE network over its existing 3G network to provide dual W-CDMA/LTE service, which will combine the benefits of LTE’s high transmission speeds with 3G’s wide-area coverage as the LTE network is expanded gradually”. And these new W-CDMA base stations with remote radio equipment (RRE) units is reported to cover half of the initial LTE stations.

The new RRE (also known as remote radio head) allows the relatively easy and efficient installation of LTE base stations to existing W-CDMA base stations (see diagrams below). Compared to existing equipment, it also helps to lower operational costs thanks to its reduced weight, size and energy consumption.

The RRE-equipped base station comprises a master unit for signal processing and maintenance functions and the RRE for modulating and demodulating both W-CDMA and LTE signals transmitted and received via antenna. The two are linked by optical fiber.