OFDM receiving circuit having multiple demodulation paths
Embodiments according to the application relate to an OFDM (orthogonal frequency division multiplexing) receiving circuit and methods thereof configured to have a plurality of demodulation paths, which can increase or improve a performance of an ADC and/or a filter.
1 . An OFDM receiving circuit comprising:
a low noise amplifier to amplify a received OFDM signal to an amplification;
a plurality of demodulation paths to receive an output signal of the low noise amplifier and to output a plurality of data, wherein a band of the OFDM signal comprises a plurality of bands each to include a plurality of sub-carriers, and each of the plurality of demodulation paths to select a signal in a band corresponding to said each of the plurality of demodulation paths from a down-converted signal of the low noise amplifier and to subject the selected signal to a digital conversion and a demodulation to output a data of the plurality of data; and
a combiner to combine the plurality of data from the plurality of demodulation paths.
2 . The circuit in accordance with claim 1 , wherein said each of the plurality of demodulation paths comprises:
a down-conversion mixer to down-convert the output signal of the low noise amplifier;
a filter to pass the signal of output signals of the down-conversion mixer in the band corresponding to one of the plurality of demodulation paths;
an ADC to digitally convert of an output of the filter; and
a demodulator to demodulate an output of the ADC.
3 . The circuit in accordance with claim 2 , wherein a pass band of the filter is configured to match the band corresponding to each of the plurality of demodulation paths.
4 . The circuit in accordance with claim 1 , comprising a single down-conversion mixer to down-convert an output signal of the low noise amplifier or a plurality of down-conversion mixers each in a corresponding one of the plurality of demodulation paths.
5 . The circuit in accordance with claim 4 , comprising an amplifier connected between the down-conversion mixer and the filter, the amplifier to amplify the output signal of the down-conversion mixer to be inputted to the filter.
6 . An OFDM receiving method comprising:
amplifying an received OFDM signal;
obtaining a plurality of digital signals from the amplified OFDM signal, wherein a band of the OFDM signal is divided into a plurality of bands, each of the plurality of bands to include a plurality of sub-carriers, and each of the plurality of digital signals is obtained by down-converting the amplified OFDM signal and subjecting a signal of the down-converted OFDM signal in one of the plurality of bands corresponding to each of the plurality of digital signals to a digital conversion;
demodulating the plurality of digital signals to obtain a plurality of data; and
combining the plurality of data to obtain a demodulated data corresponding to the received OFDM signal.
7 . The method in accordance with claim 6 , wherein the obtaining comprises:
inputting the amplified OFDM signal to a plurality of down-conversion mixer to obtain a plurality of down-converted OFDM signals;
inputting the plurality of down-converted OFDM signals to a plurality of filters configured to have different pass bands to obtain a plurality of signals having different signal bands; and
inputting the plurality of signals having the different signal bands to a plurality of ADCs to obtain the plurality of digital signals.
8 . The method in accordance with claim 6 , comprising down-converting the amplified OFDM signal using a single mixer.
9 . The method in accordance with claim 6 , comprising amplifying the down-converted OFDM signal.
10 . An OFDM receiving circuit comprising
a low noise amplifier to amplify a received OFDM signal;
a plurality of demodulation paths to receive the OFDM signal from the low noise amplifier and to output a plurality of data, wherein a band of the OFDM signal is divided into a plurality of bands, each of the plurality of bands is configured to include a plurality of sub-carriers, and the plurality of demodulation paths comprises at least one first demodulation path to process a first band of the plurality of bands and at least one second demodulation path to process a second band of the plurality of bands different from the first band; and
a combiner to combine the plurality of data from the plurality of demodulation paths.
11 . The circuit in accordance with claim 10 , wherein each of the first demodulation path and the second demodulation path comprises:
a down-conversion mixer to down-convert the OFDM signal from the low noise amplifier;
a filter to pass through a signal of an output signal of the down-conversion mixer in a corresponding band of the demodulation path;
an ADC to digitally convert a OFDM signal from the filter; and
a demodulator to demodulate an output of the ADC.
12 . The circuit in accordance with claim 10 , wherein each of the first demodulation path and the second demodulation path comprises:
a filter to pass through a signal of an output signal of the down-conversion mixer in a corresponding band of the demodulation path;
an ADC to digitally convert a OFDM signal from the filter; and
a demodulator to demodulate an output of the ADC.