Tower Mounted Amplifier

[islam wagih]

Dears,
I want to ask how TMA amplify RF signal in uplink while it is a passive element ?

[firstmaxim]

TMA is NOT a passive device; it is an amplifier with high gain and low noise figure. The TMA is mounted near the antenna, so as to curtail the noise contribution of the transmission line, and thereby improves the overall receiver noise figure. When the NF of the RX improves, its sensitivity improves, and hence its uplink coverage is enhanced.

[islam wagih]

TMA is NOT a passive device; it is an amplifier with high gain and low noise figure. The TMA is mounted near the antenna, so as to curtail the noise contribution of the transmission line, and thereby improves the overall receiver noise figure. When the NF of the RX improves, its sensitivity improves, and hence its uplink coverage is enhanced.

If it is active device, where is the power source for this TMA.

[wolverine]

A TMA is an active device as stated. The power is provided from the ground cabinet and coupled on the feeder using a bias tee. This eliminates the need to run a separate power supply line up to the TMA.

[hoangtuna]

If it is active device, where is the power source for this TMA.

I think that TMA is powered by bias t

[islam wagih]

sorry, I didn't understand.

[firstmaxim]

The power source is from the BTS. You can use the same feeder cable to transfer dc power to the TMA. This is a pretty common concept in many RF systems..you can see the BUC and LNB, both outdoor units powered from the indoor unit in VSAT systems, and also the LNA in Satellite Systems - it gets the power from the Transceiver Shelf.

[juanpico]

Islam

Hope your already understand the concept of TMA being an active device base on the comments below.

Anyway to add details, TMA reduces system noise therefore improving uplink sensitivity by having it near the antenna (having a gain that is close to feeder loss).

br//juan/rf

Dears,
I want to ask how TMA amplify RF signal in uplink while it is a passive element ?

[justdream]

Dears,

Could you share Benchmark report for adding TMA

[dimooon11]

Dears,

Could you share Benchmark report for adding TMA

Performance of TMA can be different and it depends on peculiarites at certain sites, who is manufacturer of TMA, etc.

But it s for sure that sensitivity of BTS improves hence link balance, RxLev UL, TCH drop, HO rate also improves.