3G tower mounted amplifiers

The UMTS dual TMAs represent a second generation in RFS' UMTS RF conditioning technology, providing performance in a lightweight package. In addition, the TMAs and supporting equipment are compliant with the open communications protocol defined by the Antenna Interface Standards Group (AISG), offering flexibility in implementing third generation (3G) antenna systems.

Compensating for different degrees of feeder loss in the RF chain, the amplifiers will be available in both low-gain (12 dB) and high-gain (31 dB) versions, and are characterised by low levels of transmit insertion loss and noise figure.

The low weight of the TMAs is made possible through the use of advanced filter technology. Each dual TMA comprises a single printed circuit board connected to a dual triplexer, with six air-cavity filters (36-pole) in a single filter block. The filters are made not of aluminium, but of lightweight polymer materials, and the total weight is 3 kg.

Other mechanical benefits include the 'hanging first and locking after' mounting technology and a compact housing with inline connector positions, allowing ease of installation.

The TMAs are compliant with the AISG communications protocol, which specifies the data transmission system between the base station and the active equipment located in the mast. They also each have an in-built bias-tee that, paired with a standalone modem bias-tee located in the base station, allows control signals to be sent via the RF feeder cables.

The amplifiers also come equipped with a special AISG RS485 port for connecting to antenna remote electrical tilt equipment, as well as an alarm system and auto-bypass function based on the AISG protocol.