en 5-Antenna Antenna Research Paper Research Paper <span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:black">This paper, using the circuit-geometric features of the Method of Moments (MoM),&nbsp;presents a comprehensive analytical treatment of an exponentially non-uniform helical antenna (ENH), mounted on a ground plane of finite extent. Earlier investigations reported in the literature established that the introduction of an exponential non-uniformity in the turns spacing of an otherwise uniformly wound helical antenna significantly improves its axial ratio and power gain profiles, but failed to address two important questions; one concerning the influence of the degree of non-uniformity on the antenna performance: and the other, the associated return loss profile, which is of particular importance in practical applications. It is shown in this paper, that when a properly designed impedance matching circuitry is introduced, a return loss of the ENH of close to 60 dB is achievable; without compromising axial ratio and gain performances.&nbsp;&nbsp;Indeed, axial ratio bandwidth remained unchanged at 54.55% for both the impedance-matched and unmatched ENHs, whilst maximum gain changed marginally from 14.19dB, for the unmatched ENH to 14.18dB for the impedance-matched antenna</span></span></span><span style="font-size:10.0pt"><span new="" roman="" style="font-family:" times="">.</span></span>&nbsp; Axial Mode, Exponential non-Uniformity, Helical Antenna, Impedance Matching, Return Loss. 78 90 http://ijeee.iust.ac.ir/browse.php?a_code=A-10-4516-1&slc_lang=en&sid=1 Ayotunde Abimbola Ayorinde aayorinde@unilag.edu.ng 1800319475328460013231 1800319475328460013231 No DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING, UNIVERSITY OF LAGOS, AKOKA, LAGOS, NIGERIA Sulaiman Adeniyi Adekola adekola_sulaiman@yahoo.com 1800319475328460013232 1800319475328460013232 No DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING, UNIVERSITY OF LAGOS, AKOKA, LAGOS, NIGERIA IKE MOWETE amowete@unilag.edu.ng 1800319475328460013233 1800319475328460013233 Yes DEPARTMENT OF ELECTRICAL AND ELECTRONICS ENGINEERING UNIVERSITY OF LAGOS, AKOKA,, LAGOS, NIGERIA