• Sajjad Ahmed Ghauri International Islamic University, Islamabad.



Demodulation process without the knowledge of modulation scheme requires Automatic Modulation Classification (AMC). When receiver has limited information about received signal then AMC become essential process. AMC finds important place in the field many civil and military fields such as modern electronic warfare, interfering source recognition, frequency management, link adaptation etc. In this paper we explore the use of K-nearest neighbor (KNN) for modulation classification with different distance measurement methods. Five modulation schemes are used for classification purpose which is Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM), 16-QAM and 64-QAM. Higher order cummulants (HOC) are used as an input feature set to the classifier. Simulation results shows that proposed classification method provides better results for the considered modulation formats.


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Author Biography

Sajjad Ahmed Ghauri, International Islamic University, Islamabad.

Assistant Professor 

Department of Electronics Engineering 

Faculty of Engineering & Technology 

Islamabad Pakistan 


[1] Sajjad Ahmed Ghauri, Qureshi I.M., Malik, A.N., Cheema, T.A., “A Novel Modulation Classification Approach Using Gabor Filter Network”, The Scientific World Journal (TSWJ), pp. 1-14, 2014.

[2] Xu, J., Su, W., Zhou, M.: ‘Likelihood-ratio approaches to automatic modulation classification’, IEEE Trans. Syst. Man Cybern. C, Appl. Rev., 2011, 41, (4), pp. 455–469

[3] Sajjad Ahmed Ghauri, Qureshi, I.M., “M-PAM Signals Classification
using Modified Gabor Filter Network”, Mathematical Problems in Engineering, 2015.

[4] Sajjad Ahmed Ghauri, Qureshi, I.M., Shah, I., Khan, N., “Modulation Classification using Cyclo-stationary Features on Fading Channels”, Research Journal of Applied Sciences Engineering & Technology (RJASET), Vol. 7(24), pp-5331-5339, 2014

[5] Azzouz, E.E., Nandi, A.K.: ‘Algorithms for automatic modulation recognition of communication signals’, IEEE Trans. Commun., 1998, 46, (4), pp. 431–436

[6] Wang, F., Wang, X.: ‘Fast and robust modulation classification via Kolmogorov-Smirnov test’, IEEE Trans. Commun., 2010, 58, (8), pp. 2324–2332

[7] Ho, K.C., Prokopiw, W., Chan, Y.T.: ‘Modulation identification of digital signals by the wavelet transform’, IEE Proc. Radar Sonar Navig., 2000, 147, (4), pp. 169–176

[8] Hong, L., Ho, K.: ‘Identification of digital modulation types using the wavelet transform’. Proc. of 1999 IEEE Military Communications Conf., 1999

[9] Zhao, F., Hu, Y., Hao, S.: ‘Classification using wavelet packet decomposition and support vector machine for digital modulations’, J. Syst. Eng. Electron., 2008, 19, (5), pp. 914–918

[10] Li, P., Wang, F., Wang, Z.: ‘Algorithm for modulation recognition based on high-order cumulants and subspace decomposition’. Proc. of 2006 Eighth Int. Conf. on Signal Processing, 2006

[11] Mirarab, M., Sobhani, M.: ‘Robust modulation classification for PSK/QAM/ASK using higher-order cumulants’. Proc. of 2007 Sixth Int. Conf. on Information, Communications and Signal Processing, 2007

[12] Shen, L., Li, S., Song, S., Chen, F.: ‘Automatic modulation classification of MPSK signals using high order cumulants’. Proc. of 2006 Eighth Int. Conf. on Signal Processing, 2006

[13] An, N., Li, B., Huang, M.: ‘Modulation classification of higher order MQAM signals using mixed-order moments and Fisher criterion’. Proc. of 2010 the Second Int. Conf. on Computer and Automation Engineering, 2010

[14] Shan, Z., Xin, Z., Ying, W.: ‘Improved modulation classi fication of MPSK signals based on high order cumulants’. Proc. of 2010 2nd Int. Conf. on Future Computer and Communication, 2010

[15] Swami, A., Sadler, B.: ‘Hierarchical digital modulation classification using cumulants’, IEEE Trans. Commun., 2000, 48, (3), pp. 416–429

[16] Han, G., Li, J., Chen, C.: ‘A robust MDPSK modulation classifier based on cumulants’. Proc. of 2003 17th Int. Conf. on Advanced Information Networking and Applications, 2003

[17] Pedzisz, M., Mansour, A.: ‘Automatic modulation recognition of MPSK signals using constellation rotation and its 4th order cumulant’, Digital Signal Process., 2005, 15, (3), pp. 295–304

[18] Yang, L., Ji, Z., Xu, X., Dai, X., Xu, P.: ‘Modulation classification in multipath fading environments’. Proc. of 2007 Fourth Int. Symp. on Wireless Communication Systems, 2007

[19] Wu, H.C., Saquib, M., Yun, Z.: ‘Novel automatic modulation classification using cumulant features for communications via multipath channels’, IEEE Trans. Wirel. Commun., 2008, 7, (8), pp. 3098–3105

[20] Ramkumar, B., Bose, T., Radenkovic, M.S.: ‘Robust multiuser automatic modulation classifier for multipath fading channels’. Proc. of 2010 IEEE Symp. on New Frontiers in Dynamic Spectrum, 2010

[21] Orlic, V., Dukic, M.: ‘Algorithm for automatic modulation classification in multipath channel based on sixth-order cumulants’. Proc. of 2009 Ninth Int. Conf. on Telecommunication in Modern Satellite, Cable and Broadcasting Services, 2009

[22] Orlic, V., Dukic, M.L.: ‘Multipath channel estimation algorithm for automatic modulation classification using sixth-order cumulants’, Electron. Lett., 2010, 46,

[23] Park, C., Kim, D.: ‘ A novel robust feature of modulation classification for reconfigurable software radio’, IEEE Trans. Consum. Electron., 2006, 52, (4), pp. 1193–1200

[24] Nikias, C.L., Petropuou, A.: ‘Higher-order spectral analysis’ (Prentice Hall, 1993)

[25] Stark, H., Woods, J.W.: ‘Probability and random processes with applications to signal processing’ (Prentice Hall, 2002, 3rd ed

[26] Sajjad Ahmed Ghauri, Qureshi I.M., Aziz, A., Cheema, T.A., “Classification of Digital Modulated Signals using Linear Discriminant Analysis on Faded Channel”, World Applied Sciences Journal, Vol. 29(10), pp. 1220-1227, 2014.

[27] Sajjad Ahmed Ghauri, Qureshi I.M., Malik, A.N., Cheema, T.A., “Automatic Digital Modulation Classification Technique using Higher Order Cummulants on Faded Channels”, J. Basic. Appl. Sci. Res., Vol. 4(3), pp. 1-12, 2014.


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How to Cite

Ghauri, S. A. (2016). KNN BASED CLASSIFICATION OF DIGITAL MODULATED SIGNALS. IIUM Engineering Journal, 17(2), 71–82.