In this paper, we present an experimental verification of a novel QR-TLS algorithm. Two other algorithms for direction of arrival (DOA) estimation of multiple incident source signals called multiple signal classification (MUSIC) and estimation of signal parameters via rotational invariance techniques (ESPRIT) are implemented on a National Instruments (NI) PXI platform. The proposed method is based on subspace decomposition of a received data into a signal and a noise space using QR decomposition. The angle of the signal arrival information is extracted from the signal subspace by using the method of total least squares (TLS). The algorithms are implemented in LabView NI hardware. The experimental procedures are discussed in details which includes interfacing of the uniform linear array (ULA) of antennas with the NI-PXI platform, calibrating phase differences between the RF receivers, and selecting transmitter and receiver parameters, for determining the DOAs of the multiple incident source signals. The experimental results are shown for a single and two sources lying at arbitrary angles from the array reference to verify the successful real time implementation of the proposed and other DOA estimation algorithms.
2. Paulraj, A., R. Roy, and T. Kailath, "Estimation of signal parameters via rotational invariance techniques --- ESPRIT," Nineteenth Asilomar Conference on Circuits, Systems and Computers , 83-89, 1985.
3. Yang, P., F. Yang, and Z.-P. Nie, "DOA estimation with sub-array divided technique and interpolated ESPRIT algorithm on a cylindrical conformal array antenna ," Progress In Electromagnetics Research, Vol. 103, 201-216, 2010.
4. Kim, Y.-S. and Y.-S. Kim, "Improved resolution capability via virtual expansion of array," Electronics Letters, Vol. 35, No. 19, 1596-1597, 1999.
5. Park, G.-M. and S.-Y. Hong, "Resolution enhancement of coherence sources impinge on a uniform circular array with array expansion ," Journal of Electromagnetic Waves and Applications, Vol. 21, No. 15, 2205-2214, 2007.
6. Ichige, K. and H. Arai, "Implementation of FPGA based fast DOA estimator using unitary MUSIC algorithm [cellular wireless base station applications] ," IEEE 58th Vehicular Technology Conference, VTC2003-Fall, Vol. 1, 213-217, 2003.
7. Ichige, K. and H. Arai, "Real-time smart antenna system incorporating FPGA-based fast DOA estimator," IEEE 60th Vehicular Technology Conference, VTC2004-Fall, Vol. 1, 160-164, 2004.
8. Wang, H. and M. Glesner, "Hardware implementation of smart antenna systems," Adv. Radio Sci., Vol. 4, 185-188, 2006.
9. Chen, J., J. Benesty, and Y. A. Huang, "Performance of GCC- and AMDF-based time-delay estimation in practical reverberant environments," EURASIP Journal on Advances in Signal Processing, Vol. 2005, No. 1, 25-36, 2005.
10. Hua, M.-C., C.-H. Hsu, and H.-C. Liu, "Implementation of direction-of-arrival estimator on software defined radio platform," 2012 8th International Symposium on Communication Systems, Networks & Digital Signal Processing (CSNDSP), 1-4, 2012.
11. Hou, S., S. Chang, H. Hung, and J. Chen, "DSP-based implementation of a real-time DOA estimator for underwater acoustic sources ," Journal of Marine Science and Technology, Vol. 17, No. 4, 320-325, 2009.
12. Tayem, N., M. Omer, S. Raza, and M. Lakkis, "QR-TLS ESPRIT for source localization and frequency estimations," Asilomar Conference on Signals and Systems, 1-5, 2013.
13. Trefethen, L. N. and D. Bau, "Numerical linear algebra ," Society for Industrial and Applied Mathematics (SIAM), 1997.
14. Schmidt, R., "Multiple emitter location and signal parameter estimation," IEEE Transactions on Antennas and Propagation, Vol. 34, No. 3, 276-280, 1986.