When LTELong Term Evolution standard regarding subcarrier shift and phase reset. The LTE standard requires that the uplink subcarriers be spaced on either side of DC by half the subcarrier spacing. When this is done, a phase reset is also needed after each symbol.is selected, the demodulator expects the uplink signal to comply with the
To demodulate a signal that does not shift the subcarriers by half the subcarrier spacing (and therefore does not need a phase reset), clear theparameter.
To demodulate a signal that conforms to the half subcarrier shift, but does not reset the phase each symbol, clear this parameter. The signal will then be demodulated correctly, but will show a frequency offset error of 7.5 KHz.
Downlink signals have an odd number of subcarriers, and the middle subcarrier, located at DC, is discarded, since recovering the data from a DC subcarrierIn an orthogonal frequency division multiplexing (OFDMOrthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS.) or orthogonal frequency division multiple access (OFDMA) signal, the subcarrier whose frequency would be equal to the RFRadio Frequency: A generic term for radio-based technologies, operating between the Low Frequency range (30k Hz) and the Extra High Frequency range (300 GHz). center frequency of the station. is generally difficult. In contrast, uplink signals have one less subcarrier than the corresponding downlink signal and are shifted down in frequency by half the subcarrier spacing such that the subcarriers are symmetric about DC, causing less bandwidth to be wasted.
LTE Demod Properties Dialog Box
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