Teletronics 2.4GHz 1 Watt SmartAmp User Manual
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1. General Product Description
SMART Amplifier (SMARTAMP) is a new bi-directional antenna-mount amplifier
designed to match any advanced spread spectrum system, either direct
sequence or frequency hopping, to extend the operating range of wireless
equipment. It is provided in a wide range of frequencies, such as 900 MHz, 2400
MHz, or 5800 MHz. It works in Time-Division Duplex (TDD) mode that allows the
radio device to share the antenna in different time intervals. SMARTAMP
consists of an intelligent algorithm and Automatic Gain Controlled (AGC) circuits
to maintain the output power and prevent transmit signal saturation. The input
transmit power level is sensed by the Radio Frequency (RF) sensor and the gain
is automatically adjusted to minimize the signal distortion so that the desired
signal quality can be assured.
This product has a wide range of wireless applications in Wireless Local Area
Network (WLAN), Wireless Local Loop (WLL), Wireless Internet Access (WIA),
wireless modem connection with point-to-point, point-to-multipoint, where the
Time Division Duplex (TDD) technology is used.
2. Background
In wireless applications, when longer operating range is required, the add-on
antenna amplifier and DC injector set are often a choice. Because of different site
layout and hardware configuration, it is almost impossible for amplifier
manufacture to design the amplifier and fit all applications. Typically, in most
applications, the interconnection cable could have different length from a few feet
to a few hundred feet. The attenuation between DC injector and bi-directional
amplifier could be few dB to more than 20 dB. Also, different radio modems have
different output powers. Thus, the system installer must carefully measure the
input RF power at the antenna amplifier and specify the gain of the amplifier in
order to maintain the system performance. With different systems, different
amplifiers are required. With this invention, the major difference as compared to
other existing technology, is the “SMART function” - power level detection and
automatic gain control circuit. With SmartAmp, the gain can be intelligently adapt
to the input power level in a wide range and automatically further adjusted to
accommodate the cable and connectors loss, by however length and
configuration. The output power level is monitored and maintained intelligently;
hence the desired performance can be achieved in all hardware configurations
for TDD wireless applications irrespective of installation environment.
The table on the next page summarizes the difference between SMARTAMP and
other TDD antenna-mount amplifier product.