New fully-digitalized π/4-shift QPSK modulator for personal communication terminals

Tetsu Sakata, Kazuhiko Seki, Shuji Kubota, Shuzo Kato

Research output: Contribution to journalArticlepeer-review

3 Citations (Scopus)


This paper proposes a new fully-digitalized π/4-shift QPSK modulator consisting of a digital pulse shaping filter and a baseband quadrature modulator. By employing a novel digital filter configuration, the required filter memory is reduced to just 6.25% of the conventional one. Moreover, since the proposed baseband modulation scheme does not employ analog mixers or an analog 90° divider, a very accurate, high-stable and compact modulator is realized. It is shown that the proposed scheme achieves excellent low power consumption characteristics and is more suitable for digital LSIC implementation of personal communication terminals than a direct RF modulation scheme and an analog IF modulation scheme.

Original languageEnglish
Pages (from-to)921-926
Number of pages6
JournalIEICE Transactions on Communications
Issue number7
Publication statusPublished - 1994 Jul
Externally publishedYes

ASJC Scopus subject areas

  • Software
  • Computer Networks and Communications
  • Electrical and Electronic Engineering


Dive into the research topics of 'New fully-digitalized π/4-shift QPSK modulator for personal communication terminals'. Together they form a unique fingerprint.

Cite this