16QAM definition of 16QAM in the Free Online Encyclopedia.

QAM

(1) (Quality Assessment Measurement) A system used to measure and analyze voice transmission.

(2) (Quadrature Amplitude Modulation) A modulation technique that employs both phase modulation (PM) and amplitude modulation (AM). Widely used to transmit digital signals such as digital cable TV and cable Internet service, QAM is also used as the modulation technique in orthogonal frequency division multiplexing (see OFDM). The "quadrature" comes from the fact that the phase modulation states are 90 degrees apart from each other.

Analog QAM
Analog QAM uses two carriers 90 degrees out of phase with each other. Each carrier is modulated by an analog signal, and the resulting modulated waves are combined.

Digital QAM
In digital QAM, the input stream is divided into groups of bits based on the number of modulation states used. For example, in 8QAM, each three bits of input, which provides eight values (0-7) alters the phase and amplitude of the carrier to derive eight unique modulation states (see example below). In 64QAM, each six bits generates 64 modulation states; in 128QAM, each seven bits generates 128 states, and so on. See modulation.

Analog QAM

Analog QAM modulates two carriers 90 degrees out of phase with each from two analog input streams. The modulated carriers are combined and transmitted.

Digital QAM

In this 8QAM example, three bits of input generate eight different modulation states (0-7) using four phase angles on 90 degree boundaries and two amplitudes: one at 50% modulation; the other at 100% (4 phases X 2 amplitudes = 8 modulation states). QAM examples with more modulation states become extremely difficult to visualize.

Quadrature PSK

Quadrature PSK (QPSK) is like 4QAM without amplitude modulation. QPSK uses four phase angles to represent each two bits of input; however, the amplitude remains constant.

QAM

(communications)

quadrature amplitude modulation

1.		QAM - Quadrature Amplitude Modulation.
2.		QAM - Quality Assurance Management.

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No references found	The supported modulation schemes are QPSK, 16QAM and 64QAM with variable rates for the encoder as shown in Table 1. A new fairness-oriented packet scheduling scheme with reduced channel ... by Nonchev, Stanislav; Valkama, Mikko / International Journal of Communications, Network and Systems Sciences (IJCNS) Upstream channels may deliver 500 Kbps to 10 Mbps from homes by using 16QAM or QPSK (Quadrature Phase Shift Key) modulation techniques. Cable Data Network by Anil Satram / Telecommunications industry community 69GHz Bandwidth: 5MHz, 10MHz Wireless Access Method: 512/1024 FFT OFDMA Modulation method: 64QAM(1), 16QAM, QPSK(2) Antenna: 2x2 STC/MIMO (supports MatrixA & MatrixB) Antenna Impedance: 50 Ohm Diversity: Antenna Diversity Transmission Standard: IEEE 802. Fujitsu Launches World's Smallest RF Module for Mobile WiMAX Devices; ... by JCN Newswires	14.4 1440p 1541 1550 nm 1581 16 bit 16 bits 16-bit 16-bit application 16-bit color 16-bit computing 16-bit driver 16-bit sound 16-bit version 16-way 16:9 16000 16450 16550 16550A 16650 16750C 16C550 16C750 16C850 16QAM 1802 1ClickCharge 1D 1NF 1PH 1RU 1TBS 1U 1x 1xRTT 2 2,2'-azobisisobutyronitrile 2,2'-bipyridine 2,2'-dihydroxy-4,4'-dimethoxybenzophenone 2,2'-dipyridyl 2,2,2-trichloroethanol 2,2-bis-1,1-dichloroethane 2,2-diethyl-1,3-propanediol 2,2-dimethyl-1,3-dioxolane-4-methanol 2,3-benzopyrrole 2,3-butanediol 2,3-dimethylbutane 2,3-pyridinedicarboxylic acid 2,4'-dihydroxyacetophenone 2,4,5-T	169.254.0.0 16A 16APSK 16C550 16C750 16C850 16CIF 16CIF 16CIF 16CIF 16CIF 16CIF 16DAPSK 16mo 16mo 16mo 16o 16o 16P4A 16PF 16QAM 16s 16s 16s gene 16s gene 16S rDNA 16S rDNA 16th 16th 16th Amendment 16th April 16th August 16th century 16th century 16th December 16th February 16th January 16th July 16th June 16th March 16th millenium BC 16th millennium BC 16th note 16th November 16th October 16th President of the United States 16th President of the United States 16th Seanad 16th September 16va

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The supported modulation schemes are QPSK, 16QAM and 64QAM with variable rates for the encoder as shown in Table 1.

A new fairness-oriented packet scheduling scheme with reduced channel ... by Nonchev, Stanislav; Valkama, Mikko / International Journal of Communications, Network and Systems Sciences (IJCNS)

Upstream channels may deliver 500 Kbps to 10 Mbps from homes by using 16QAM or QPSK (Quadrature Phase Shift Key) modulation techniques.

Cable Data Network by Anil Satram / Telecommunications industry community

69GHz Bandwidth: 5MHz, 10MHz Wireless Access Method: 512/1024 FFT OFDMA Modulation method: 64QAM(**1), 16QAM, QPSK(**2) Antenna: 2x2 STC/MIMO (supports MatrixA & MatrixB) Antenna Impedance: 50 Ohm Diversity: Antenna Diversity Transmission Standard: IEEE 802.

Fujitsu Launches World's Smallest RF Module for Mobile WiMAX Devices; ... by JCN Newswires

QAM (redirected from 16QAM)

QAM
(redirected from 16QAM)