Resultados da pesquisa

...-spaced [[Orthogonality|orthogonal]] ''sub-carriers''. Each sub-carrier is modulated with a conventional modulation scheme (such as [[quadrature amplitude modul ...using many slowly-modulated [[narrowband]] signals rather than one rapidly-modulated [[wideband]] signal. Low symbol rate makes the use of a [[guard interval]]

...ng and interference which often plagues conventional broadcasting on these frequency ranges. ...cations and Media Authority]], announced that it had "placed an embargo on frequency bands potentially suitable for use by broadcasting services using Digital R

...[Hertz|kHz]] into the household wiring at the transmitter. The carrier is modulated by digital signals. Each receiver in the system has an address and can be i PLC modems transmit in medium and high frequency (1.6 to 30 [[Megahertz|MHz]] electric [[carrier wave|carrier]]). The [[symm

...The transponder 'retransmits' the signals back to Earth but at a different frequency band (to avoid interference with the uplink signal), typically in the [[C b ...signals are transmitted, and converts the block of frequencies to a lower frequency range in the [[L band|L-band]] range. The evolution of LNBs was one of nece

...enables the tag to send and receive data. Passive, low- (135 kHz) and high-frequency (13.56 MHz) tags usually have a coiled antenna that couples with the coiled ...m a reader, usually at the same carrier frequency. The reflected signal is modulated to transmit data.