Morse code
Morse code is a method of transmitting text information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment. The ...
Morse code - Wikipedia
Olivia MFSK
Olivia MFSK is an amateur radioteletype protocol designed to work in difficult (low signal-to-noise ratio plus multipath propagation) conditions on shortwave bands. The signal can still be properly co...
Telegraph key
Telegraph key is a general term for any switching device used primarily to send Morse code. Similar keys are used for all forms of manual telegraphy, such as in ‘wire’ or electrical telegraph and ‘wi...
Telegraph key - Wikipedia
Link adaptation
Link adaptation, or adaptive modulation and coding (AMC), is a term used in wireless communications to denote the matching of the modulation, coding and other signal and protocol parameters to the con...
MDC-1200
MDC (Motorola Data Communications), also known as Stat-Alert, MDC-1200 and MDC-600, is a Motorola two-way radio low-speed data system using audio frequency shift keying, (AFSK). MDC-600 uses a 600 bau...
Q code
The Q code is a standardized collection of three-letter message encodings, also known as a brevity code, all of which start with the letter "Q", initially developed for commercial radiotelegraph commu...
MPH (ATSC)
MPH (Mobile-Pedestrian-Handheld) inband mobile digital television is a technology jointly developed by Harris Corporation, LG Electronics, Inc. and its U.S. research subsidiary, Zenith Electronics. Th...
Hierarchical modulation
Hierarchical modulation, also called layered modulation, is one of the signal processing techniques for multiplexing and modulating multiple data streams into one single symbol stream, where base-laye...
Hierarchical modulation - Wikipedia
Pulse-position modulation
Pulse-position modulation (PPM) is a form of signal modulation in which M message bits are encoded by transmitting a single pulse in one of possible time-shifts. This is repeated every T seconds, su...
Higher-order modulation
Higher-order modulation is a type of digital modulation usually with an order of 4 or higher. Examples: quadrature phase-shift keying (QPSK), and m-ary quadrature amplitude modulation (m-QAM).
SITOR
SITOR (SImplex Teletype Over Radio) is a system for transmitting text messages. Although it uses the same frequency-shift keying (FSK) modulation used by regular radioteletype (RTTY), SITOR uses erro...
Multiple frequency-shift keying
Multiple frequency-shift keying (MFSK) is a variation of frequency-shift keying (FSK) that uses more than two frequencies. MFSK is a form of M-ary orthogonal modulation, where each symbol consists of ...
MBOC
Multiplexed binary offset carrier (MBOC) modulation is a modulation proposed for Galileo and modernized GPS signals, which combines a sine binary offset carrier SinBOC(1,1) signal with a SinBOC(6,1) ...
Samuel Morse
Samuel Finley Breese Morse (April 27, 1791 – April 2, 1872) was an American painter and inventor. After having established his reputation as a portrait painter, in his middle age Morse contributed to...
Samuel Morse - Wikipedia
Amateur Radio Emergency Service
In the United States and Canada, the Amateur Radio Emergency Service (ARES) is a corps of trained amateur radio operator volunteers organized to assist in public service and emergency communications. ...
Amateur Radio Emergency Service - Wikipedia
On-off keying
On-off keying (OOK) denotes the simplest form of amplitude-shift keying (ASK) modulation that represents digital data as the presence or absence of a carrier wave. In its simplest form, the presence o...
MT63
MT63 is a digital radio modulation mode for transmission in high-noise situations developed by Pawel Jalocha SP9VRC. MT63 is designed for keyboard-to-keyboard conversation modes, on HF amateur radio b...
Amplitude and phase-shift keying
Amplitude and phase-shift keying or asymmetric phase-shift keying (APSK), is a digital modulation scheme that conveys data by changing, or modulating, both the amplitude and the phase of a reference...
Phase-shift keying
Phase-shift keying (PSK) is a digital modulation scheme that conveys data by changing, or modulating, the phase of a reference signal (the carrier wave).Any digital modulation scheme uses a finite num...
CLOVER2000
CLOVER is the name of a series or class of modem modulation techniques (“waveforms”) specifically designed for use over high frequency (HF) radio systems.
In ARQ mode, all CCB’s (CLOVER Control Bl...
Constellation diagram
A constellation diagram is a representation of a signal modulated by a digital modulation scheme such as quadrature amplitude modulation or phase-shift keying. It displays the signal as a two-dimensi...
Constellation diagram - Wikipedia
Modulation error ratio
The modulation error ratio or MER is a measure used to quantify the performance of a digital radio transmitter or receiver in a communications system using digital modulation (such as QAM). A signal s...
Z code
Z Code (like Q Code and X Code) is a set of codes used in CW, TTY and RTTY radio communication. Actually, there are different sets of Z-codes: one originally developed by Cable & Wireless Ltd., fo...
Discrete Multi-Tone
Orthogonal frequency-division multiplexing (OFDM) is a method of encoding digital data on multiple carrier frequencies. OFDM has developed into a popular scheme for wideband digital communication, use...
Discrete Multi-Tone - Wikipedia
Amplitude-shift keying
Amplitude-shift keying (ASK) is a form of amplitude modulation that represents digital data as variations in the amplitude of a carrier wave.In an ASK system, the binary symbol 1 is represented by tra...
Amplitude-shift keying - Wikipedia
Radioteletype
Radioteletype (RTTY) is a telecommunications system consisting originally of two or more electromechanical teleprinters in different locations connected by radio rather than a wired link. These machi...
Radioteletype - Wikipedia
Russian Morse code
The Russian Morse code approximates the Morse code for the Latin alphabet. To memorize the codes, mnemonics are used, called "melodies" (напевы).A "melody" for a morse code for a character is a phrase...
AMTOR
AMTOR (Amateur Teleprinting Over Radio) is a type of telecommunications system that consists of two or more electromechanical teleprinters in different locations that send and receive messages to one ...
Signal lamp
A signal lamp (sometimes called an Aldis lamp, named after Arthur Cyril Webb Aldis who invented a widely used design) is a visual signaling device for optical communication (typically using Morse code...
Signal lamp - Wikipedia