Modular base station with variable communication capacity

Abstract

The present invention provides a base station architecture that is modular in configuration, lowering the initial cost of implementing a new CDMA telecommunication system for a defined geographical region while allowing for future capacity. The scalable architecture is assembled from a digital base station unit that is configured to support a plurality of simultaneous wireless calls connecting to a conventional public switched telephone network. For initial startup, two base station units are deployed for redundancy in case of a single failure. Additional base station units may be added when the need arises for extra traffic capacity. If sectorization is required, the base station units may be directionally oriented. Coupled to and remote from each base station unit are two amplified antenna modules that contain an omni-directional or an external directional antenna, a high power RF amplifier for transmitted frequencies and a low noise amplifier for received frequencies. A separate power supply module capable of supporting two base station units provides continued service in the event of a mains power outage.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to communication systems. More specifically, the invention relates to a communication system using a code division multiple access air interface between a plurality of individual subscribers distributed within a cellular community and a plurality of small capacity base stations, some colocated per cell to increase operational economy in proportion to the number of subscribers.[0003]2. Description of the Prior Art[0004]Advanced cellular communication makes use of a state of the art technique known as code division multiplexing, or more commonly, as code divisional multiple access or CDMA. An example prior art communication system is shown in FIG. 1.[0005]CDMA is a communication technique in which data is transmitted with a broadened band (spread spectrum) by modulating the data to be transmitted with a pseudo-noise signal. The data signal to be transmitted may have a bandwidth of only a few ...

AI Technical Summary

Benefits of technology

This approach reduces initial installation costs while enabling scalable capacity growth, maintaining service reliability and efficiency in handling increased traffic without significant fixed costs, allowing for flexible expansion as subscriber needs evolve.

Problems solved by technology

For the reverse-link, a common pilot signal is not feasible.

Typically, only non-coherent detection techniques are suitable to establish reverse-link communications.

Prior art CDMA communication systems have been designed and sized to immediately handle many simultaneous communications and are therefore costly start-up installations for the service provider.

These systems have not addressed the need for a flexible base station architecture that permits a cost effective, small scale initial installation that can accommodate future subscriber growth.

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