Français
5. Digital modulation strategy
For a long time, broadcast transmitters were amplitude modulated by controlling the supply voltage to the final stage (figure 19 ). This classic modulation method, mainly used in tube equipment under the name of anode control modulation, has very good linearity and stability, but limited efficiency.
Because of the class C of the RF final stage, η 2 = 0.9 is usually achieved. But the efficiency η 1 is due to the class B of the AF stages limited to just 0.5.
The typical efficiency of all amplification stages is given by :
The Ultimate Scientific and Technical Reference
This article is included in
Electronics
This offer includes:
Knowledge Base
Updated and enriched with articles validated by our scientific committees
Services
A set of exclusive tools to complement the resources
Practical Path
Operational and didactic, to guarantee the acquisition of transversal skills
Doc & Quiz
Interactive articles with quizzes, for constructive reading
Digital modulation strategy
N-type direct coupling – 1
Bibliography
Standardization
International Telecommunication Union (ITU)
Consultative Committee for Radiocommunications (CCIR)
SM. 328-10 (12/99). Emission spectra and bandwidths.
Institute of Electricity and Electronic Engineers (IEEE)
IEEE - 587. Lightning protection.
International Electronics Commission (IEC)
- Règles...
Organizations
International Telecommunication Union (ITU)
International Telecommunication Union (ITU)
Telecommunications Regulatory Authority (ART)
International Electronical...
Manufacturers - Suppliers
Thomcast
Rhode & Schwartz
Telefunken
...
The Ultimate Scientific and Technical Reference
