White Paper: SISO To MIMO: Moving Communications From Single-Input Single-Output To Multiple-Input Multiple-Output

By Mark Elo, Keithley Instruments

Commercial radio technology has reached an inflection point, similar to the transition from analog to digital, when we invented a whole range of digital technology. Now we are moving from single carrier technologies, where we transmit one digital symbol at a time, to a new paradigm, where we are potentially transmitting hundreds of symbols simultaneously. The technology of choice for this broadband connection is based on a modulation scheme called orthogonal frequency division multiplexing (OFDM). OFDM transmits hundreds of symbols simultaneously, yet at a low rate per symbol.