Mobile Network Glossary: 36 Signal Terms Explained Simply

Talk about mobile signal for long enough and you run into a wall of jargon: dBm, VoLTE, Band 40, RSRP, AGC, LPDA. This glossary explains the terms you are most likely to meet when troubleshooting weak network or choosing a signal booster in India, each in a sentence or two of plain English. Bookmark it, and use the links to go deeper.

Signal measurement terms

dBm

The unit for received signal power, relative to one milliwatt. Mobile readings are negative: −70 dBm is strong, −110 dBm is weak. Every 10 dB is a tenfold change in power. Check yours with our signal strength checker.

dB (decibel)

A ratio, used for gain and loss. A booster with 60 dB gain multiplies signal power a million times; a wall with 10 dB loss lets through a tenth of the signal.

RSRP (Reference Signal Received Power)

The main 4G signal-strength number, in dBm. About −80 dBm or better is excellent; weaker than −110 dBm is poor.

RSRQ (Reference Signal Received Quality)

A 4G quality number in dB that falls when the cell is busy or interference is high. About −10 dB or better is good.

SINR (Signal to Interference plus Noise Ratio)

How clearly your wanted signal stands out from interference and noise, in dB. Higher is better; it is the best predictor of data speed. All three are explained in RSRP, RSRQ and SINR explained.

RSSI (Received Signal Strength Indicator)

Total power received on a channel, including noise and interference. It is used for 2G/3G and Wi-Fi; on 4G, RSRP is more useful.

ASU (Arbitrary Strength Unit)

A number some Android phones show alongside dBm, derived from it. Higher ASU means stronger signal.

Signal bars

The phone's simplified display of signal strength. Bars are not standardised between brands, so use dBm for real comparisons.

Network and spectrum terms

Band

A defined block of radio frequencies used for mobile service, identified by a number (Band 3, Band 40). Your phone uses one band at a time. See how to find which band your phone uses.

Band 5 / Band 8 (850 / 900 MHz)

Low bands with long range and good wall penetration. Band 5 is used by Jio; Band 8 by Airtel, Vi and BSNL.

Band 3 (1800 MHz)

The main 4G band for most operators in Indian cities, balancing range and capacity.

Band 1 (2100 MHz)

Used by Airtel, Vi and BSNL for 3G and 4G. More capacity, shorter range.

Band 40 (2300 MHz)

A high-capacity 4G band used by Jio and Airtel. It carries lots of data but weakens quickly indoors.

Telecom circle

The licence region an operator's spectrum is assigned in, often a state or a metro. Band usage can differ between circles.

2G / 3G / 4G (LTE) / 5G

Generations of mobile technology. 4G LTE carries most calls and data in India today. 5G uses different, mostly higher, frequencies that fade faster indoors; phones fall back to 4G when 5G is weak.

VoLTE (Voice over LTE)

Voice calls carried over the 4G network instead of older 2G/3G. Most Indian calls now use VoLTE, so weak indoor 4G means poor calls, even on 5G phones. More on our 5G phones page.

VoWiFi (Wi-Fi calling)

Calls carried over your broadband Wi-Fi instead of the tower. A useful backup; compared in signal booster vs Wi-Fi calling.

Cell / sector

The area served by one antenna on a tower. A tower usually has three sectors, each pointing a different way.

Handover

Your phone moving its connection from one cell to another. Too many handovers, common on high floors, cause dropped calls.

Congestion

When too many users share a cell, so everyone gets slower data even with strong signal. See weak signal vs congestion.

Dead zone

A spot with little or no usable signal, such as a basement, lift, inner room or metal shed.

Downtilt

The slight downward angle of tower antennas, which focuses signal on the ground and lower floors.

Interference

Unwanted signal on the same frequency, often from other cells, that lowers quality (SINR).

Signal booster terms

Signal booster / repeater / amplifier

A system that picks up existing outdoor mobile signal, amplifies it and rebroadcasts it indoors. It can't create signal where none exists. See how a signal booster works.

Gain

How much a booster or antenna strengthens the signal, in dB (boosters) or dBi (antennas). More gain covers more area or works with weaker outdoor signal.

AGC (Automatic Gain Control)

A booster feature that turns amplification up or down automatically to keep output steady and avoid overload.

Oscillation (feedback)

When the indoor antenna's signal leaks back into the outdoor antenna, like a microphone squealing near a speaker. It is prevented by keeping the two antennas well separated.

Uplink / downlink

Downlink is tower-to-phone; uplink is phone-to-tower. A booster amplifies both directions.

Outdoor (donor) antenna

The antenna on the roof or balcony that receives the tower's signal.

LPDA antenna

Log-Periodic Dipole Array: a directional, high-gain outdoor antenna that is aimed at one distant tower. See the LPDA outdoor antenna.

Panel (patch) antenna

A flat, directional antenna that can be used outdoors facing a nearby tower or indoors on a wall. See the panel antenna.

Dome antenna

A ceiling-mounted indoor antenna that spreads signal in all directions. See the indoor dome antenna.

Splitter

Divides the booster's output between two or three indoor antennas to cover more rooms or floors.

Coaxial cable (LMR-300 / LMR-400)

The cable connecting the antennas and booster. LMR-400 is thicker and loses less signal over long runs. See LMR-400 cable.

Coverage area

The indoor area, in sq.ft, a booster can serve. SIGLIFT kits range from 1,500 to 10,000 sq.ft depending on model and outdoor signal.

Multi-band booster

A booster that amplifies several bands at once, so it can serve several operators. Compare models in the kit comparison table.

Quick reference table

Term	Good value or rule of thumb
RSRP	−90 dBm or better indoors is comfortable
RSRQ	−10 dB or better
SINR	13 dB or higher
Outdoor signal for a booster	1–2 bars on the roof; around −100 dBm or better is ideal
Antenna separation	As far apart as practical, ideally separated by a floor or roof slab

Frequently asked questions

Is a signal booster the same as a repeater?

Yes, in everyday use. Both terms describe a system that receives mobile signal outside, amplifies it and rebroadcasts it indoors. "Network booster" and "signal amplifier" mean the same thing.

What is a good dBm for mobile signal?

On 4G, about −80 to −90 dBm is good, −100 dBm is weak but usable, and below about −110 dBm calls start failing.

What does Band 40 mean on my phone?

Your phone is using the 2300 MHz 4G band, common for Jio and Airtel. It offers high capacity but weakens quickly indoors, so phones often switch to a lower band deeper inside buildings.

Do I need to understand all this to buy a booster?

No. Tell SIGLIFT your operator, floor area and where the signal drops, and our experts will choose the right kit for you.

Still have a question about a term or a reading? Ask a SIGLIFT signal expert on WhatsApp or call +91-9650237601. Or let the Signal Booster Finder pick a kit for you.