Estimation of Diversity and MIMO Parameters of Multiple Planar-Inverted F-Antenna in the Presence of Users' Body

Abstract

In this chapter, the estimation of diversity and multiple-input multiple-output (MIMO) parameters is carried out in the presence of the users’ body. The diversity parameters such as mean effective gain, envelope correlation coefficient, and effective diversity gain are calculated. Further, MIMO parameters such as channel capacity and multiplexing efficiency are also estimated in a mobile environment and human body. The design of the antenna is considered from the published article of the same author. Mainly, the antenna is designed for MIMO applications, and study has been carried out in the free space only. The published antenna design cannot be applicable on the real-time platform until and unless its diversity and MIMO parameters should follow the defined criteria of the Cellular Telecommunications Industry Association (CTIA). In this study, three common user modes of the mobile phone are taken named as “specific anthropomorphic mannequin head and personal digital assistant (PDA) hand (voice position),” “PDA hand (data position),” and “dual hands (read position).” The estimation of diversity and MIMO parameters is done for three different user positions. All the parameters are estimated by positioning the antenna at the top and bottom of a printed circuit board (PCB). This study was carried out to check the optimum location of the antennas on the mobile phone PCB. Moreover, the specific absorption rate (SAR) will be a crucial parameter when we consider the case of a mobile phone. Therefore, the designed antenna should follow the guidelines of the SAR limit on the actual platform. Hence, in this chapter, the calculation of 2SAR for the proposed antenna is carried out and tabulated. In the case of a MIMO antenna, SAR of one antenna may affect the SAR of another antenna. Therefore, SAR of a MIMO antenna can be estimated in terms of SAR to peak location spacing ratio, and it should be less than 0.3 according to the Federal Communications Commission. Furthermore, the amount of power loss plays a vital role in the close proximity of human body to estimate the performance of the MIMO antenna. Therefore, the parameters, that is, total radiated power and power loss are also estimated in the user’s body. Based on the above study and estimated parameters, it can be concluded that the designed antenna will be suitable for the real-time application because all the estimated parameters should follow the critical standard limit of CTIA.