Title :
Implementation of adaptive modulation on the Sunrise software radio
Author :
Jain, Payal ; Buehrer, R. Michael
Author_Institution :
Mobile & Portable Radio Res. Group, Virginia Polytech. Inst. & State Univ., USA
Abstract :
In this paper, we investigate the implementation issues associated with adaptive modulation using pilot symbol assisted modulation based channel estimators for Rayleigh fading environments. The scheme will be implemented on the BAE System´s Sunrise receiver (which has TI´s C67 DSP). Sunrise has a download capability enhanced by the WJ-8629A developer´s kit, which provides the end user the capability to create algorithms capable of addressing evolving requirements related to receiver filtering, demodulation, decoding and analysis. Modulation is adapted on the basis of the channel SNR estimated from the received signal. Three sets of switching levels for modulation schemes were assumed and correspond to SNR at which QPSK, 16QAM, 64 QAM achieve ∼0.1%, 1% and 10% BER in a Gaussian channel. We also investigate the impact of channel estimators, channel quality estimation and the effect of frame delays on adaptive modulation.
Keywords :
Gaussian channels; Rayleigh channels; adaptive modulation; channel estimation; decoding; demodulation; error statistics; fast Fourier transforms; interpolation; quadrature amplitude modulation; quadrature phase shift keying; radio receivers; software radio; 16QAM; 64 QAM; BER; Gaussian channel; QPSK; Rayleigh fading environments; Sunrise software radio; WJ-8629A developer kit; adaptive modulation; channel SNR estimation; channel quality estimation; decoding; demodulation; download capability; frame delays; modulation based channel estimators; pilot symbol assisted modulation; receiver filtering; Algorithm design and analysis; Decoding; Delay estimation; Demodulation; Digital signal processing; Filtering algorithms; Quadrature phase shift keying; Rayleigh channels; Receivers; Software radio;
Conference_Titel :
Circuits and Systems, 2002. MWSCAS-2002. The 2002 45th Midwest Symposium on
Print_ISBN :
0-7803-7523-8
DOI :
10.1109/MWSCAS.2002.1187059