Carrier Multiplexing

Carrier Multiplexing
When network managers solicit user input on network build-outs, one of the most common demands is
for more speed. The hunger for increased data transmissions has driven a host of technologies to
increase speed. OFDM takes a qualitatively similar approach to Multilink Point-to-Point Protocol (MPPP)-
when one link isn't enough, use several in parallel.
OFDM is closely related to plain old frequency division multiplexing (FDM). Both divide the available
bandwidth into slices called carriers or subcarriers and make those carriers available as distinct channels
for data transmission. OFDM boosts throughput by using several subcarriers in parallel and multiplexing
data over the set of subcarriers.
Traditional FDM was widely used by first-generation mobile telephones as a method for radio channel
allocation. Each user was given an exclusive channel, and guard bands were used to ensure that
spectral leakage from one user did not cause problems for users of adjacent channels.[8]