A LTE repeater (also known as cell phone signal booster or amplifier) is a type of bi-directional amplifier used to improve UE reception and address coverage issues.
LTE repeater does not just do power amplification of the received signal from LTE eNB or LTE Base Station, it also selects the band specific signals using one duplexer. After amplification it transmits the signal back to the UEs(User Equipments) or Mobile Subscribers.
How it affects SNR:
With received weak signal amplification, noise power also gets amplified. Due to this noise amplification, SNR(Signal to Noise Ratio) will not be improved and further may get degraded.
Duplexer is used in case of FDD LTE repeater, other wise for TDD repeater, duplexer is replaced with band pass filter.
Both indoor and outdoor cellular repeater deployments are possible, but a majority of deployments occur inside buildings where coverage is weakened by attenuation from building materials.
Guide to buy:
If one wants to buy LTE repeater, following things should be taken care of:
- LTE Repeater Band
- TDD or FDD
- Gain of Repeater
- Antenna installation space, one outside the room and one inside
- Power supply requirement for the Repeater
- Supports downlink only or uplink, downlink both
- Signal to Noise Ratio
- LTE FDD System Capacity and Throughput Calculations
- LTE TDD Special Subframe and Its significance for Cell Size
- LTE Control Plane and User Plane Latency Calculation (FDD)
- LTE Spectral Efficiency Calculation