dBm

Reference Website
https://en.wikipedia.org/wiki/DBm



dBm (sometimes dBmW or decibel-milliwatts) is an abbreviation for the power ratio in decibels (dB) of the measured power referenced to one milliwatt (mW). It is used in radio, microwave and fiber optic networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form. Compare dBW, which is referenced to one watt (1000 mW).

Since it is referenced to the watt, it is an absolute unit, used when measuring absolute power. By comparison, the decibel (dB) is a dimensionless unit, used for quantifying the ratio between two values, such as signal-to-noise ratio.

In audio and telephony, dBm is typically referenced relative to a 600 ohm impedance,[1] while in radio frequency work dBm is typically referenced relative to a 50 ohm impedance.


Power level

	Power	Notes
80 dBm	100 kW	Typical transmission power of FM radio station with 50-kilometre (31 mi) range
62 dBm	1.588 kW = 1,588 W	1,500 W is the maximum legal power output of a U.S. ham radio station.[3]
60 dBm	1 kW = 1,000 W	Typical combined radiated RF power of microwave oven elements
55 dBm	~300 W	Typical single-channel RF output power of a Ku-Band GEO-stationary satellite
50 dBm	100 W	Typical total thermal radiation emitted by a human body, peak at 31.5 THz (9.5 micron) Typical maximum output RF power from a ham radio HF transceiver
40 dBm	10 W	Typical PLC (Power Line Carrier) transmit power
37 dBm	5 W	Typical maximum output RF power from a handheld ham radio VHF/UHF transceiver
36 dBm	4 W	Typical maximum output power for a Citizens' band radio station (27 MHz) in many countries
33 dBm	2 W	Maximum output from a UMTS/3G mobile phone (Power class 1 mobiles) Maximum output from a GSM850/900 mobile phone
30 dBm	1 W = 1,000 mW	DCS or GSM 1,800/1,900 MHz mobile phone. EIRP IEEE 802.11a (20 MHz-wide channels) in either 5 GHz Subband 2 (5,470–5,725 MHz) provided that transmitters are also IEEE 802.11h-compliant, or U-NII-3 (5,725–5,825 MHz). The former is EU only, the latter is US only.
29 dBm	794 mW
28 dBm	631 mW
27 dBm	500 mW	Typical cellular phone transmission power Maximum output from a UMTS/3G mobile phone (Power class 2 mobiles)
26 dBm	400 mW
25 dBm	316 mW
24 dBm	251 mW	Maximum output from a UMTS/3G mobile phone (Power class 3 mobiles) 1,880–1,900 MHz DECT (250 mW per 1,728 kHz channel). EIRP for Wireless LAN IEEE 802.11a (20 MHz-wide channels) in either the 5 GHz Subband 1 (5,180–5,320 MHz) or U-NII-2 & -W ranges (5,250–5,350 MHz & 5,470–5,725 MHz respectively). The former is EU only, the latter is US only.
23 dBm	200 mW	EIRP for IEEE 802.11n Wireless LAN 40 MHz-wide (5 mW/MHz) channels in 5 GHz subband 4 (5,735–5,835 MHz, US only) or 5 GHz subband 2 (5,470–5,725 MHz, EU only). Also applies to 20 MHz-wide (10 mW/MHz) IEEE 802.11a Wireless LAN in 5 GHz Subband 1 (5,180–5,320 MHz) if also IEEE 802.11h compliant (otherwise only 3 mW/MHz → 60 mW when unable to dynamically adjust transmission power, and only 1.5 mW/MHz → 30 mW when a transmitter also cannot dynamically select frequency).
22 dBm	158 mW
21 dBm	125 mW	Maximum output from a UMTS/3G mobile phone (Power class 4 mobiles)
20 dBm	100 mW	EIRP for IEEE 802.11b/g Wireless LAN 20 MHz-wide channels in the 2.4 GHz Wi-Fi/ISM band (5 mW/MHz). Bluetooth Class 1 radio. Maximum output power from unlicensed AM transmitter per U.S. Federal Communications Commission (FCC) rules 15.219.[4]
19 dBm	79 mW
18 dBm	63 mW
17 dBm	50 mW
15 dBm	32 mW	Typical Wireless LAN transmission power in laptops
10 dBm	10 mW
7 dBm	5.0 mW	Common power level required to test the automatic gain control circuitry in an AM receiver
6 dBm	4.0 mW
5 dBm	3.2 mW
4 dBm	2.5 mW	Bluetooth Class 2 radio, 10 m range
3 dBm	2.0 mW
2 dBm	1.6 mW
1 dBm	1.3 mW
0 dBm	1.0 mW = 1,000 µW	Bluetooth standard (Class 3) radio, 1 m range
−1 dBm	794 µW
−3 dBm	501 µW
−5 dBm	316 µW
−10 dBm	100 µW	Maximum received signal power of wireless network (802.11 variants)
−20 dBm	10 µW
−30 dBm	1.0 µW = 1,000 nW
−40 dBm	100 nW
−50 dBm	10 nW
−60 dBm	1.0 nW = 1,000 pW	The Earth receives one nanowatt per square metre from a magnitude +3.5 star[5]
−70 dBm	100 pW
−73 dBm	50.12 pW	"S9" signal strength, a strong signal, on the S-meter of a typical ham or shortwave radio receiver
−80 dBm	10 pW
−100 dBm	0.1 pW	Minimum received signal power of wireless network (802.11 variants)
−111 dBm	0.008 pW = 8 fW	Thermal noise floor for commercial GPS single channel signal bandwidth (2 MHz)
−127.5 dBm	0.178 fW = 178 aW	Typical received signal power from a GPS satellite
−174 dBm	0.004 aW = 4 zW	Thermal noise floor for 1 Hz bandwidth at room temperature (20 °C)
−192.5 dBm	0.056 zW = 56 yW	Thermal noise floor for 1 Hz bandwidth in outer space (4 kelvins)
−∞ dBm	0 W	Zero power is not well-expressed in dBm (value is negative infinity)