Andrew Node C, User Manual

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2 Introduction
Page 15
2. INTRODUCTION
2.1. PURPOSE
Wireless communication systems provide a two-way information transfer (voice and
data) between a base station and multiple mobiles within a given area.
Environmental variables such as physical structures both man-made (buildings) and
natural (mountains) attenuate signals in the transmission path, which reduce the
transport signal’s strength. This attenuation leads to a reduction in quality and data
rate and eventually prohibits the system’s use entirely. The Node M and Node C are
specifically designed to extend coverage, enhance quality, and increase air-interface
capacity.
In the downlink (DL), the Node M and Node C picks up signals coming from the base
station, filters them, amplifies them, and retransmits them to the mobile. In the uplink
(UL), it picks up signals from the mobile, filters them, amplifies them, and retransmits
them to the base station. The Node M and Node C constantly monitors the quality of
the signals passing through it, while simultaneously electronically decreasing
isolation requirements.
2.2. THE NODE M AND NODE C (NODE M/C) NETWORK ELEMENT
Node M and Node C are primary network elements, capable of enhancing up to 20
MHz of continuous spectrum. Their primary function is to increase the signal strength
between multiple mobiles and a base station in areas where basic voice or high-
speed data transmission is not available. They may be used for basic coverage,
signal reinforcement, and cell shaping, which can increase a network’s coverage
area, data rate, and capacity.
The Node M is a dedicated UMTS device, but the Node C operates with CDMA
technology. However, several enhancers operating at different frequencies and
technologies may share the same hardware (cables and antennas) via a crossband
coupler.
The Node M or Node C may be set-up locally or remotely. A circuit switch or packet
data modem may be connected to an integrated controller. This provides the network
management system with on-demand, alarm generated, or heartbeat monitoring via
the always-connected packet features. The Node M and Node C have features and
functions that may be monitored and changed by the operators via a web-based
browser remotely or locally, or via the SNMP based OMC software platform. The
graphical interfaces of Node M and Node C provide a setup menu including a setup
wizard which allows both setup and monitoring capability without any equipment
required apart from a laptop or PC.
The Node M and Node C network elements are self-diagnosing, self-adaptive, and
virtually maintenance-free.
In the following, the expression Node M/C stands for Node M and Node C.