Amplifiers suit in-building application


Point-of-interface bi-directional amplifiers for 800 and 900MHz

Wireless technology group, Radio Frequency Systems (RFS) has launched two new band-selective bi-directional amplifiers designed for the 800 MHz and 900 MHz frequency bands. The compact I-BSA800-1 and I-BSA900-1 amplifiers feature finely adjustable frequency bandwidth selectivity via a unique PC-based configuration software tool. The uplink/downlink frequency ranges supported are 824-849 MHz/869-894 MHz and 890-915 MHz/935-960 MHz respectively for the I-BSA800-1 and I-BSA900-1.

“As the new I-BSAs are sub-band selective they are the ideal complements to RFS’s broadband I-BDA bi-directional amplifier family,” said Stefan Lehmann, RFS Area Product Manager Wireless Distributed Communication Systems. Separate gain adjustment for uplink and downlink is achievable while maintaining the same power output in both directions. As a result, the I-BSA is the ideal point-of-interface (POI) for in-building systems founded on external antennas.
According to Lehmann, the I-BSAs have been designed to receive and re-transmit signals derived from antennas outside a building, and amplify only the selected bands for in-building distribution. With the RFS I-BSA series providing the building’s primary POI amplification and band selection, localized signal amplification can be provided throughout the building using RFS’s broadband I-BDA units. “Whether you have a strong or weak link from outside the building, regardless of what’s behind the amplifier, the RFS I-BSAs provide a great deal of flexibility in planning and system set-up,” said Lehmann.
For the European and Asian markets, the I-BSA900-1 has been specifically designed for global system for mobile communications (GSM) in the 900 MHz band. Similarly, for the American and Asian networks, the I-BSA800-1 is tailored to suit services in the cellular 800 MHz band (code division multiple access (CDMA), time division multiple access (TDMA) and the analogue advanced mobile phone standard (AMPS)).
Allowing precision adjustments, the I-BSA800-1 and I-BSA900-1 feature variable frequency bandwidth selection from 0.03 MHz to 25 MHz, and 0.2 MHz to 25 MHz, respectively. “Such fine-tuning is possible just by connecting a laptop to the device,” said Lehmann. The user-friendly programming software--which allows authorized access only, for reasons of security and asset management--provides the ability to configure the I-BSA’s frequency bandwidth, amplification and gain. Uplink and downlink gain is adjustable in 2 dB steps between 20 and 60 dB, while output power is 22 dBm (in both uplink and downlink) at maximum gain.