?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aulast=Liu&rft.au=Liu%2C+Z&rft.aufirst=Z&rft.atitle=Modulator-free+quadrature+amplitude+modulation+signal+synthesis&rft.date=2014&rft.issn=2041-1723&rft.title=Nature+Communications&rft.volume=5&rft.genre=article