Carrierless Modulation Systems
Newer forms of radio communication (such as spread spectrum and ultra-wideband) do not transmit a conventional carrier wave, nor does OFDM (which is used in DSL and in the European standard for HDTV).
- OFDM may be thought of as an array of symmetrical carrier waves. The rules governing carrier-wave propagation affect OFDM differently than 8VSB.
- Some forms of spread spectrum transmission (and most forms of ultra-wideband) are mathematically defined as being devoid of carrier waves. Transmitter implementations typically produce residual carriers which may (or may not) be detectable or transmitted.
Read more about this topic: Carrier Wave
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