Methods and systems for generating a low peak-to-average power ratio (PAPR) data and reference signal
Embodiments of the present disclosure relate to systems and methods to generate a signal in a communication network. The method comprises filtering a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) data signal, and one of a DFT-S-OFDM and orthogonal frequency division multiplexing (OFDM) reference signal (RS) using a data filter and a RS filter respectively, to produce filtered data signal and filtered RS. The RS filter has one to one relationship with the data filter. Thereafter, port mapping the filtered RS to a corresponding port assigned to the transmitter to obtain port mapped filtered RS, wherein the port mapped filtered RS comprises a first subset of non-zero locations comprising of the filtered RS values and a second subset of zero locations comprising of zero values.
1. A method for generating a signal in a communication network, the method comprising:
filtering, by a transmitter, a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) data signal using a data filter to generate a filtered data signal;
filtering, by the transmitter, a DFT-S-OFDM reference signal (RS) using a RS filter to generate a filtered RS, wherein the RS filter has a one-to-one relationship with the data filter; and
port mapping, by the transmitter, the filtered RS to a corresponding port assigned to the transmitter to obtain a port mapped filtered RS, wherein the port mapped filtered RS comprises a first subset of locations comprising the filtered RS values and a second subset of locations, each with a value of zero.
2. The method of claim 1 , comprising:
generating the DFT-S-OFDM RS using a reference sequence modulated by π/2 rotated Binary Phase Shift Keying (BPSK).
3. The method of claim 1 , comprising:
generating the DFT-S-OFDM RS using a reference sequence modulated by a Zadoff-Chu (ZC) sequence.
4. The method of claim 1 , comprising:
generating the DFT-s-OFDM data signal using a data sequence modulated by π/2 BPSK.
5. The method of claim 1 , comprising:
generating the DFT-s-OFDM data signal by rotating a modulated data sequence.
6. The method of claim 5 , wherein the modulated data sequence is a BPSK data sequence.
7. The method of claim 5 , wherein the rotation is performed on consecutive samples.
8. The method of claim 5 , wherein the rotation is sequentially incremented by 90°.
9. The method of claim 1 , comprising:
indicating characteristics of one of the RS filter and the data filter to a receiver.
10. The method of claim 1 , wherein a time domain impulse response of the RS filter is equal to a time domain impulse response of the data filter.
11. A system for generating a signal in a communication network, the system comprising:
a data filter to generate a filtered data signal from a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) data signal;
a reference signal (RS) filter to generate a filtered RS from a DFT-S-OFDM RS, wherein the RS filter has a one-to-one relationship with the data filter; and
a transmitter to port map the filtered RS to an assigned port to obtain a port mapped filtered RS, wherein the port mapped filtered RS comprises a first subset of locations comprising the filtered RS values and a second subset of locations, each with a value of zero.
12. The system of claim 11 , wherein the DFT-S-OFDM RS comprises a reference sequence modulated by π/2 rotated Binary Phase Shift Keying (BPSK).
13. The system of claim 11 , wherein the DFT-S-OFDM RS comprises a reference sequence modulated by a Zadoff-Chu (ZC) sequence.
14. The system of claim 11 , wherein the DFT-s-OFDM data signal comprises a data sequence modulated by π/2 BPSK.
15. The system of claim 11 , wherein the DFT-s-OFDM data signal comprises a data sequence that is modulated and rotated.
16. The system of claim 15 , wherein the data sequence is BPSK modulated.
17. The system of claim 15 , wherein the rotation is performed on consecutive samples.
18. The system of claim 15 , wherein the rotation is sequentially incremented by 90°.
19. The system of claim 11 , wherein the transmitter is configured to indicate characteristics of one of the RS filter and the data filter to a receiver.
20. The system of claim 11 , wherein a time domain impulse response of the RS filter is equal to a time domain impulse response of the data filter.