modulation
Let an agent explain modulation and its kinds, relay analogue and digital schemes, their trade-offs and standards from telecommunications references, describe applications, and distinguish modulation from coding, multiplexing and the musical or other senses of modulation.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify
Researched by: Claude
Purpose and description
Let an agent explain modulation and its kinds, relay analogue and digital schemes, their trade-offs and standards from telecommunications references, describe applications, and distinguish modulation from coding, multiplexing and the musical or other senses of modulation.
The process of varying one or more properties of a carrier signal, such as amplitude, frequency or phase, in accordance with an information signal so that it can be transmitted over a channel, in analogue forms such as AM and FM, digital forms such as phase-shift and quadrature amplitude modulation, pulse modulation, spread spectrum techniques such as direct-sequence spread spectrum, multicarrier schemes with subcarriers, and line codes such as eight-to-fourteen modulation used on optical discs; standardised radio modes combine modulation with protocols.
What it is for: Carrying information on signals.
It can be explain the concept and kinds; relay schemes and trade-offs; describe applications; distinguish related concepts.
Distinguishing features
Carrier variation
Analogue or digital
Bandwidth and power trade-offs
Standardised schemes
What it looks like
Not a visible object; variations in a signal.
Physical character
QAM orders in use: up to 4096 points - in cable and Wi-Fi
FM broadcast deviation: 75 kHz - typical
EFM code rate: 8 to 14 bits - plus merging bits
How it is recognised
Varying a carrier to carry information
AM, FM, PSK, QAM, pulse modulation, direct-sequence spread spectrum, subcarriers, eight-to-fourteen modulation, standardised radio modes
Channel coding adds redundancy; multiplexing shares a channel; musical modulation changes key
Related models
is a kind of - process in registry terms
is reversed by - at the receiver
is combined with - in modern systems
is contrasted with - a homonym
In practice
Families and kinds
analogue modulation such as AM, FM and PM
digital modulation such as ASK, FSK, PSK and QAM
pulse modulation such as PCM, PWM and PPM
spread spectrum including direct-sequence and frequency hopping
multicarrier modulation such as OFDM with subcarriers
line codes and recording codes such as eight-to-fourteen modulation
Standards and regulation
ITU radio regulations and emission designations
Standards such as DVB, LTE, 5G NR and Wi-Fi specifying modulation
Optical disc standards for EFM
Failure modes and hazards
Confusing modulation with coding or multiplexing
Interference and spectral inefficiency
Mixing the telecommunications and musical senses
Also called
+9
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.modulation
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Understand What modulation is.
Science.
Definition
Definition.
Definition
Definition.
- What is modulation, and how does it differ from coding, multiplexing and musical modulation? definition
- Is the question about telecommunications modulation, a specific scheme or another sense? boundary
Kinds
Kinds.
Kinds
Kinds.
- How do analogue, digital, pulse, spread spectrum, multicarrier and line-code modulation differ? definition
- Which entry fits the specific scheme? action
Engineer Design.
Science.
Tradeoffs
Trade-offs.
Tradeoffs
Tradeoffs.
- How do bandwidth, power, noise and error rate trade off across schemes? provenance
- Which references are standard? provenance
Implementation
Implementation.
Implementation
Implementation.
- How are modulators and demodulators implemented in hardware and software-defined radio? provenance
- Which sources are cited? provenance
Apply Applications.
Application.
Radio
Radio and mobile.
Radio
Radio.
- Which modulation schemes are used in broadcasting, mobile networks, Wi-Fi and satellite, and what are standardised radio modes? provenance
- Which entry fits the specific standard? action
Storage
Storage and wired.
Storage
Storage.
- How are codes such as eight-to-fourteen modulation used on optical discs, and what schemes carry data over cable and fibre? provenance
- Which entry fits eight-to-fourteen modulation? action
Context History.
Context.
History
History.
History
History.
- How did modulation develop from spark and AM radio to FM, digital and OFDM? provenance
- Which entry fits the history of radio? action
Theory
Theory.
Theory
Theory.
- How do Shannon capacity and signal space describe modulation limits? provenance
- Which entry fits information theory? action
What the second pass must settle
- Should QAM and OFDM be separate primary entries?
- How should telecommunications standards be linked?
- The registry entry has merged aliases naming schemes and codes; should they be split off?