Extended lapped transforms for digital multicarrier modulation
نویسندگان
چکیده
In today's multicarrier modulation systems such as orthogonal frequency division multiplexing (OFDM) or discrete multitone (DMT), modulation is accomplished digitally by the use of the inverse discrete Fourier transform (IDFT). Instead of the IDFT, any other orthogonal transform can be used. In this paper a multicarrier scheme based on extended lapped transforms (ELT) is investigated. With the ELT, a better spectral containment of the subchannels is achieved, which also leads to a superior power spectral density of the multicarrier signal. Further, the ELT multicarrier modulation is shown to be more robust against frequency selective interferers present on the transmission channel .
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