Yu.K. Vyboldin – Ph.D.(Eng.), Associate Professor, Department of Electronic Systems, St. Petersburg Mining University E-mail: Y.Vyboldin@mail.ru

K.V. Zaichenko – Dr.Sc.(Eng.), Professor, Head of Department of Medical Radio Electronics, Saint-Petersburg State University of Aerospace Instrumentation

E-mail: kvz_k41@aanet.ru

The algorithm for receiving signals with quadrature amplitude modulation in communication channels with fading is synthesized. To estimate the channel parameters, a special group of pilot symbols consisting of the signal elements with maximum energy is transmitted. This evaluation is performed on the duration of their transmission interval, within one frame, which shortens the decision time. A modified generalized maximum likelihood criterion was used to synthesize optimal decision schemes for QAM reception.

1. Hanzo L., Ng S.X., Keller T., Webb W. Quadrature amplitude modulation. John Wiley & Sons, Ltd. 2004. 1105 p.
2. Borgne M. Comparison of high-Level modulation schemes for high-capacity digital radio systems // IEEE Trans. Commun. May 1985. V. COM-33. № 5. P. 442−449.
3. Andronov I.S., Vy’boldin Yu.K., Malinin S.I. Potenczial’naya pomexoustojchivost’ priema signalov KAM po pozicziyam // Dep. VINITI. 1999. № 473-V99.
4. Webb W.T., Hanzo L., Steele R. Bandwidth_efficient QAM schemes for Rayleigh_fading channels // IEE Proc. June 1991. Pt I. V. 138. № 3. P. 169−175.
5. Andronov I.S., Vy’boldin Yu.K., Malinin S.I. Algoritmy’ demodulyaczii dvoichny’x kanalov sistem KAM pri raznesennom prieme v sredax s neizvestny’mi parametrami // Radiotexnika. 1996. № 11. S. 32−35.
6. Xia B, Wang J. Effect of channel estimation error on QAM systems with antenna diversity // IEEE Trans. Commun. March 2005. V. 53. № 3. P. 481−488.
7. Bateman A., McGeehan J. Data tranmissions over UHF fading mobile radio channels // Proceeding of IEE. 1984. V. 131. Pt F. P. 364−374.
8. Cavers J.K. An analysis of pilot symbol assisted modulation for Rayleigh fading channels // IEEE Trans. Veh. Technol. November 1991. V. VT-40. № 4. P. 686−693.
9. Albattat H.J., AlSabbagh M.H., Alseyab S.A. State-space approaches for modeling reduction of pilot symbol assisted modulation and their impact on the channel estimation // International Journal of Wireless & Mobile Networks. August 2012. V. 4. № 4. P. 181−193.
10. Barazideh R., Seyfe B. Adaptive PSAM in SIMO systems with imperfect CSI in Rayleigh fading channels // International Journal of Hybrid Information Technology. April 2010. V. 3. № 2. P. 9−23.
11. Fink L.M. Teoriya peredachi diskretny’x soobshhenij. M.: Sov. radio. 1970. 731 s.
12. Vy’boldin Yu.K., Krivoshejkin A.V., Nurmuxamedov L.X. Metody’ obrabotki diskretny’x signalov v sistemax peredachi informaczii. SPb.: Izd-vo GIKIT. 2015. 320 s.