Method and System for Designing a Waveform for Data Communication

Abstract

Embodiments herein disclose a method and system for designing a waveform for data communication. The method includes applying, by a phase rotation applying unit, a constellation specific phase rotation between consecutive data symbols in a data stream to obtain a constellation rotated data stream. Further, the method includes introducing, by a frequency domain pulse shaping filter, an inter symbol interference (ISI) between modulated data symbols of the constellation rotated data stream, such that the ISI develops the waveform of the constellated rotated data stream to be transmitted.

What is claimed is: 
     
         1 - 24 . (canceled) 
     
     
         25 . A method for generating a waveform for data communication, the method comprising:
 applying, by a transmitter, a constellation specific phase rotation between consecutive data symbols in a data stream to obtain a constellation rotated data stream;   obtaining, by the transmitter, a Discrete Fourier transform (DFT) spread signal from the constellation rotated data stream in frequency domain using a DFT, wherein said DFT is at least one of a one-sided DFT and a two-sided DFT;   mapping, by the transmitter, the DFT spread signal using one of a localized subcarriers and distributed subcarriers, to produce a mapped spread signal;   applying, by the transmitter, a frequency domain pulse shaping filter to the mapped DFT spread signal to obtain a filtered spread signal, wherein the frequency domain pulse shaping filter is a DFT of samples of a time domain pulse shaping filter, wherein said DFT is one of a one-sided DFT and a two-sided DFT; and   processing, by the transmitter, the filtered spread signal to generate a waveform.   
     
     
         26 . The method as claimed in  claim 25 , wherein the DFT spread signal is one of DFT of the constellation rotated data stream and periodic extension of the DFT of the constellation rotated data stream in the frequency domain. 
     
     
         27 . The method as claimed in  claim 25 , wherein the size of the DFT of the samples of a time domain pulse shaping filter is less than or equal to the length of DFT spread signal. 
     
     
         28 . The method as claimed in  claim 25 , wherein the size of the DFT of the samples of a time domain pulse shaping filter is equal to the size of the constellation rotated data stream. 
     
     
         29 . The method as claimed in  claim 25 , wherein the samples of a time domain pulse shaping filter includes only causal samples. 
     
     
         30 . The method as claimed in  claim 25 , wherein the samples of a time domain pulse shaping filter includes both causal and non-causal samples. 
     
     
         31 . The method as claimed in  claim 25 , wherein the size of the non-zero values of a time domain pulse shaping filter is two. 
     
     
         32 . The method as claimed in  claim 25 , wherein the size of the non-zero values of the samples of a time domain pulse shaping filter is at least three. 
     
     
         33 . The method as claimed in  claim 25 , wherein the constellation specific phase rotation is 90 degrees and the constellation is BPSK. 
     
     
         34 . The method as claimed in  claim 25 , wherein the method comprises adding at least one of a cyclic prefix and a cyclic suffix to the data stream after performing an Inverse Fourier transform on the filtered spread signal, to obtain a time domain filtered spread signal. 
     
     
         35 . A transmitter, wherein the transmitter comprises:
 a phase rotator operable to apply a constellation specific phase rotation between consecutive data symbols in a data stream to obtain a constellation rotated data stream;   a controller operable to obtain a Discrete Fourier transform (DFT) spread signal from the constellation rotated data stream in frequency domain using a DFT, wherein said DFT is at least one of a one-sided DFT and a two-sided DFT, and wherein the controller is operable to map the DFT spread signal, using one of a localized subcarriers and distributed subcarriers, to produce a mapped spread signal; and   a frequency domain pulse shaping filter operable to filter the mapped DFT spread signal to obtain a filtered spread signal, wherein the frequency domain pulse shaping filter is a DFT of samples of a time domain pulse shaping filter, and wherein said DFT is one of a one-sided DFT and a two-sided DFT, and wherein the filtered spread signal is processed to generate a waveform.   
     
     
         36 . The transmitter as claimed in  claim 35 , wherein the DFT spread signal is one of DFT of the constellation rotated data stream and periodic extension of the DFT of the constellation rotated data stream in the frequency domain. 
     
     
         37 . The transmitter as claimed in  claim 35 , wherein the size of the DFT of the samples of a time domain pulse shaping filter is less than or equal to the length of DFT spread signal. 
     
     
         38 . The transmitter as claimed in  claim 35 , wherein the size of the DFT of the samples of a time domain pulse shaping filter is equal to the size of the constellation rotated data stream. 
     
     
         39 . The transmitter as claimed in  claim 35 , wherein the samples of a time domain pulse shaping filter includes only causal samples. 
     
     
         40 . The transmitter as claimed in  claim 35 , wherein the samples of a time domain pulse shaping filter includes both causal and non-causal samples. 
     
     
         41 . The transmitter as claimed in  claim 35 , wherein the size of the non-zero values of a time domain pulse shaping filter is two. 
     
     
         42 . The transmitter as claimed in  claim 35 , wherein the size of the non-zero values of the samples of a time domain pulse shaping filter is at least three. 
     
     
         43 . The transmitter as claimed in  claim 35 , wherein the constellation specific phase rotation is 90 degrees and the constellation is BPSK. 
     
     
         44 . The transmitter as claimed in  claim 35 , wherein the transmitter comprises adding at least one of a cyclic prefix and a cyclic suffix to the data stream after performing an Inverse Fourier transform on the filtered spread signal, to obtain a time domain filtered spread signal.