RSRP−44 → −140 dBm
Reference Signal Received PowerAverage power of the reference signals across the channel. The single best gauge of raw signal strength — closer to zero is stronger.
Anatomy of a signal
Your phone is a radio in constant conversation with the towers around it. Here's how to read what it's actually saying — the frequencies, the bands, and the numbers that describe connection quality.
Frequency
Reach versus capacity
A radio wave's frequency sets its character. Low frequencies travel far and slip through obstacles but carry less data. High frequencies move enormous data but fade over short distances. Every band is a point on this trade-off.
← CoverageCapacity →
600 MHzLow-bandMiles of reach. Punches through walls. Modest capacity.
1.9 GHzMid-bandThe everyday workhorse — balance of reach and speed.
3.5 GHzC-bandThe 5G sweet spot: fast, with usable coverage.
28 GHzmmWaveBlazing gigabit speeds, measured block by block.
Quality metrics
How strong, how clean?
Strength and quality are different things. Drag the meter to see how RSRP — the core measure of received power — maps to real-world experience.
-85dBmGood
RSRP · Reference Signal Received Power−120−110−100−90−80−44
RSRQ−3 → −20 dB
Reference Signal Received QualityQuality of the reference signal relative to total received power. Reveals interference and load that RSRP alone hides.
SINR−20 → +30 dB
Signal to Interference + Noise RatioHow far the wanted signal rises above noise and neighboring cells. The strongest predictor of achievable throughput.
RSSI−50 → −110 dBm
Received Signal Strength IndicatorWideband power of everything in the channel — signal, noise and interference combined across all resource blocks.
Cell identifiers
Where you are on the grid
The integer that pins the exact carrier frequency and, with it, the band.
The licensed block of spectrum the cell transmits in — e.g. B13, n78.
Network-wide unique identifier for the specific cell (sector) you are camped on.
A 0–503 code that separates adjacent cells over the air; reused far apart.
Groups cells into a paging area so the network can find your device.
Channel width (1.4–100 MHz) — wider channels carry proportionally more data.
Want to resolve a channel number yourself? Open the EARFCN calculator →
Lineage
Five generations of radio
GSM · CDMA
Digital voice and SMS. The first packet data trickled in via GPRS/EDGE.
UMTS · HSPA
Mobile internet arrives — a few Mbps, enough for the early smartphone.
LTE · LTE-A
True mobile broadband. Carrier aggregation stacks bands for 100s of Mbps.
NR FR1 · FR2
Sub-6 GHz plus mmWave. Multi-gigabit peaks and far lower latency.
See it live on your own phone.
LTE Discovery surfaces every one of these readings in real time.