Abstract
In this paper we propose the design of an orthogonal precoder, in conjunction with optimal windowing, for reduction in out of band power in primary users’ (PUs) frequency bands in OFDM based cognitive radio systems. First we derive the power spectral density expression to calculate the interference power in the PUs frequency bands. We then construct an interference minimization problem which is called a generalized Hermitian eigenvalue problem with an orthogonality constraint. The resulting precoding, in conjunction with optimal windowing, reduces the interference power when compared to only precoding and only windowing, at the cost of spectral efficiency.
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References
Mahmoud, H., Yucek, T., & Arslan, H. (2009). OFDM for cognitive radio: Merits and challenges. IEEE Wireless Communications, 16(2), 6–15.
Chung, C.-D. (2006). Spectrally precoded OFDM. IEEE Transactions on Communications, 54(12), 2173–2185.
Zhang, J., Huang, X., Cantoni, A., & Guo, Y. (2012). Sidelobe suppression with orthogonal projection for multicarrier systems. IEEE Transactions on Communications, 60(2), 589–599.
Zheng, Y., Zhong, J., Zhao, M., & Cai, Y. (2012). A precoding scheme for N-continuous OFDM. IEEE Communications Letters, 16(12), 1937–1940.
Van De Beek, J., & Berggren, F. (2008). Out-of-band power suppression in OFDM. IEEE Communications Letters, 12(9), 609–611.
Rady, A., Shokair, M., El-Rabaie, E.-S., & ElKorany, A. (2015). Efficient technique for sidelobe suppression and PAPR reduction in OFDM-based cognitive radios. Wireless Personal Communications, 83(1), 215–230.
Luo, J., Kortke, A., & Keusgen, W. (2014). Guardband optimization for cellular systems applying raised cosine windowed OFDM. Wireless Personal Communications, 78(2), 1375–1390.
Lin, Y.-P., & Phoong, S.-M. (2003). OFDM transmitters: Analog representation and DFT-based implementation. IEEE Transactions on Signal Processing, 51(9), 2450–2453.
Xu, R., & Chen, M. (2009). A precoding scheme for DFT-based OFDM to suppress sidelobes. IEEE Communications Letters IEEE, 13(10), 776–778.
van Waterschoot, T., Le Nir, V., Duplicy, J., & Moonen, M. (2010). Analytical expressions for the power spectral density of CP-OFDM and ZP-OFDM signals. IEEE Signal Processing Letters, 17(4), 371–374.
Wu, T.-W., & Chung, C.-D. (2014). Spectrally precoded DFT-based OFDM and OFDMA with oversampling. IEEE Transactions on Vehicular Technology, 63(6), 2769–2783.
Xu, R., Chen, M., Zhang, J., Wu, B., & Wang, H. (2012). Spectrum sidelobe suppression for discrete Fourier transformation-based orthogonal frequency division multiplexing using adjacent subcarriers correlative coding. IET Communications, 6(11), 1374–1381.
Xu, R., & Chen, M. (2008). Spectral leakage suppression for DFT-based OFDM via adjacent subcarriers correlative coding. In IEEE Global Telecommunications Conference, GLOBECOM, pp. 1 –5.
Lin, Y.-P., & Phoong, S.-M. (2005). Window designs for DFT-based multicarrier systems. IEEE Transactions on Signal Processing, 53(3), 1015–1024.
Gert Cuypers, G. Y., Vanbleu, K., & Moonen, M. (2006). Intra-symbol windowing for egress reduction in DMT transmitters. EURASIP Journal on Applied Signal Processing, 2006, 1–9.
Seyedi, A. (2006). WLC32-2: Windowed OFDM for spectrum agile radios. In IEEE Global Telecommunications Conference, GLOBECOM, pp. 1 –5.
Yu, L., Rao, B., Milstein, L., & Proakis, J. (2010). Reducing out-of-band radiation of OFDM-based cognitive radios. In IEEE Eleventh International Workshop on Signal Processing Advances in Wireless Communications (SPAWC), 2010, June 2010, pp. 1–5.
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Sharique, M., Chaturvedi, A.K. Optimal Precoding in Conjunction with Windowing for Reduction in OOB Power of OFDM Based CR Systems. Wireless Pers Commun 91, 679–689 (2016). https://doi.org/10.1007/s11277-016-3487-2
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DOI: https://doi.org/10.1007/s11277-016-3487-2