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Correlation coefficient calculations for MIMO antenna systems: a comparative study

Published online by Cambridge University Press:  04 September 2017

Mohammad S. Sharawi ,
Abdelmoniem T. Hassan  and
Muhammad U. Khan
Mohammad S. Sharawi*
Affiliation:
Department of Electrical Engineering, King Fahd University of Petroleum and Minerals Dhahran, Dhahran, Al-Sharqia 31261, Saudi Arabia
Abdelmoniem T. Hassan
Affiliation:
Department of Electrical Engineering, King Fahd University of Petroleum and Minerals Dhahran, Dhahran, Al-Sharqia 31261, Saudi Arabia
Muhammad U. Khan
Affiliation:
SEECS, National University of Sciences & Technology (NUST), H-12, Islamabad, Pakistan
*
Corresponding author: M.S. Sharawi Email: [email protected]
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Abstract

The correlation coefficient (ρ) is an important metric for the evaluation of multiple-input–multiple-output (MIMO) antenna systems because it describes the relationship between the channels in a particular propagation environment. Highly correlated channels will degrade the MIMO system performance. Various methods to calculate ρ are analyzed in this work using three different types of antennas with different efficiencies and radiating properties. While the field-based method for finding ρ gives the most accurate results and should be used all the time. It is independent of antenna efficiency. The the S-parameter-based method might give reasonable results only when the antenna efficiency is very high and the patterns are separated in space, but in most cases, it underestimates ρ values and thus is not a reliable method and should be avoided. Incorporating the antenna efficiency can improve the ρ estimates using the S-parameters method under some specific conditions. The equivalent circuit method provides reasonable results for symmetric antenna structures only, and is the most complex in formulation. As part of the evaluation, two existing methods incorporating the radiation efficiency of the antennas are generalized to N-ports for the first time. Although less accurate than the field-based method, these extensions allow the evaluation of ρ for N-port antennas using only the radiation efficiency and the S-parameters of the antenna. The effect of the beam tilts on ρ estimation is investigated for the first time.

Keywords

Correlation coefficientMIMOIsolationEfficiencyPrinted antennas
Type
Research Papers
Information
International Journal of Microwave and Wireless Technologies , Volume 9 , Issue 10 , December 2017 , pp. 1991 - 2004
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2017 

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References

REFERENCES

[1] Vaughan, R.G.; Andersen, J.B.: Antenna diversity in mobile communications. IEEE Trans. Veh. Technol., 36 (4) (1987), 149–172.CrossRefGoogle Scholar
[2] Blanch, S.; Romeu, J.; Corbella, I.: Exact representation of antenna system diversity performance from input parameter description. Electron. Lett., 39 (9) (2003), 705–707.CrossRefGoogle Scholar
[3] Stjernman, A.: Relationship between radiation pattern correlation and scattering matrix of lossless and lossy antennas. Electron. Lett., 41 (12) (2005), 678–680.CrossRefGoogle Scholar
[4] Hallbjorner, P.: The significance of radiation efficiencies when using S-parameters to calculate the received signal correlation from two antennas. IEEE Antennas Wireless Propag. Lett., 4 (2005), 97–99.CrossRefGoogle Scholar
[5] Li, H.; Lin, X.; Lau, B.K.; He, S.: Equivalent circuit based calculation of signal correlation in lossy MIMO antennas. IEEE Trans. Antennas Propag., 61 (10) (2013), 5214–5222.CrossRefGoogle Scholar
[6] Yun, J.X., Vaughan, R.G.: Space efficiency of multiple element antennas. IEEE Trans. Antennas Propag., 60 (6) (2012), 3066–3071.Google Scholar
[7] Yun, J.X.; Vaughan, R.G.: MEA efficiency and impact on diversity and capacity. IEEE Trans. Antennas Propag., 60 (2) (2012), 529–539.CrossRefGoogle Scholar
[8] Razmhosseini, M.; Vaughan, R.G.: Accuracy of numerical modelling for evaluation of an integrated diversity wireless system on a small PCB, in 2015 IEEE Int. Symp. on Antennas and Propagation & USNC/URSI National Radio Science Meeting, Vancouver, BC, 2015, 1230–1231.CrossRefGoogle Scholar
[9] Bhattacharya, A.; Vaughan, R.G.: Daughter board antenna for compact polarization diversity on MIMO devices, in 2015 IEEE Int. Symp. on Antennas and Propagation & USNC/URSI National Radio Science Meeting, Vancouver, BC, 2015, 1218–1219.Google Scholar
[10] Li, H.; Lin, X.; Lau, B.K.; He, S.: Calculating signal correlation in lossy dipole arrays using scattering parameters and efficiencies, in 2013 7th European Conf. on Antennas and Propagation (EuCAP), Gothenburg, 2013, 519–523.Google Scholar
[11] Ogawa, K.; Matsuyoshi, T.; Monma, K.: An analysis of the performance of a handset diversity antenna influenced by head, hand, and shoulder effects at 900 MHz: Part II—correlation characteristics. IEEE Trans. Veh. Technol., 50 (3) (2001), 845–853.CrossRefGoogle Scholar
[12] Yeap, S.B.; Chen, X.; Dupuy, J.A.; Chiau, C.C.; Parini, C.G.: Integrated Diversity Antenna for Laptop and PDA Terminal in a MIMO System. IEE Proc. – Microw. Antennas Propag., 152 (6) (2005), 495–504.CrossRefGoogle Scholar
[13] Chiu, C.Y.; Yan, J.B.; Murch, R.D.: Compact three-port orthogonally polarized MIMO antennas. IEEE Antennas Wireless Propag. Lett., 6 (2007), 619–622.Google Scholar
[14] Ding, Y.; Du, Z.; Gong, K.; Feng, Z.: A four-element antenna system for mobile phones. IEEE Antennas Wireless Propag. Lett., 6 (2007), 655–658.Google Scholar
[15] Gao, Y.; Chen, X.; Ying, Z.; Parini, C.: Design and performance investigation of a dual-element PIFA array at 2.5 GHz for MIMO terminal. IEEE Trans. Antennas Propag., 55 (12) (2007), 3433–3441.Google Scholar
[16] Głogowski, R.; Peixeiro, C.: Multiple printed antennas for integration into small multistandard handsets. IEEE Antennas Wireless Propag. Lett., 7 (2008), 632–635.Google Scholar
[17] Li, H.; Xiong, J.; He, S.: A compact planar MIMO antenna system of four elements with similar radiation characteristics and isolation structure. IEEE Antennas Wireless Propag. Lett., 8 (2009), 1107–1110.Google Scholar
[18] Su, S.W.: High-gain dual-loop antennas for MIMO access points in the 2.4/5.2/5.8 GHz bands. IEEE Trans. Antennas Propag., 58 (7) (2010), 2412–2419.Google Scholar
[19] Cui, S.; Liu, Y.; Jiang, W.; Gong, S.X.: Compact dual-band monopole antennas with high port isolation. Electron. Lett., 47 (10) (2011), 579–580.Google Scholar
[20] Ling, X.M.; Li, R.L.: Novel dual-band MIMO antenna array with low mutual coupling for portable wireless devices. IEEE Antennas Wireless Propag. Lett., 10 (2011), 1039–1042.Google Scholar
[21] Sharawi, M.S.; Iqbal, S.S.; Faouri, Y.S.: An 800 MHz 2×1 compact MIMO antenna system for LTE handsets. IEEE Trans. Antennas Propag., 59 (8) (2011), 3128–3131.CrossRefGoogle Scholar
[22] Lee, J.M.; Kim, K.B.; Ryu, H.K.; Woo, J.M.: A compact ultra wideband MIMO antenna with WLAN band-rejected operation for mobile devices. IEEE Antennas Wireless Propag. Lett., 11 (2012), 990–993.Google Scholar
[23] Li, J.F.; Chu, Q.X.; Huang, T.G.: A compact wideband MIMO antenna with two novel bent slits. IEEE Trans. Antennas Propag., 60 (2) (2012), 482–489.Google Scholar
[24] Kulkarni, A.N.; Sharma, S.K.: Frequency reconfigurable microstrip loop antenna covering LTE bands with MIMO implementation and wideband microstrip slot antenna all for portable wireless DTV media player. IEEE Trans. Antennas Propag., 61 (2) (2013), 964–968.Google Scholar
[25] Karimian, R.; Oraizi, H.; Fakhte, S.; Farahani, M.: Novel F-shaped quad-band printed slot antenna for WLAN and WiMAX MIMO systems. IEEE Antennas Wireless Propag. Lett., 12 (2013), 405–408.CrossRefGoogle Scholar
[26] Fernandez, S.C.; Sharma, S.K.: Multiband printed meandered loop antennas with MIMO implementations for wireless routers. IEEE Antennas Wireless Propag. Lett., 12 (2013), 96–99.Google Scholar
[27] Wallace, J.W.; Jensen, M.A.: Termination-dependent diversity performance of coupled antennas: network theory analysis. IEEE Trans. Antennas Propag., 52 (1) (2004), 98–105.Google Scholar
[28] Frei, J.; Cai, X.; Muller, S.: Multiport S-parameter and T-parameter conversion With symmetry extension. IEEE Trans. Microw. Theory Tech., 56 (11) (2008), 2493–2504.Google Scholar