Abstrakt

Accurate Antenna Isolation Technique for Mitigation of CDMA Interference in a Co-Site Urban Environment

Okorogu V. N, Onoh G.N, Ekeh James, Alor Michael.

This Work developed an accurate and efficient Antenna Isolation model to minimize interference in cohabiting Networks that used co-site parameters in the formulation of the mathematical model. The Work determined the maximum radius of co-site cell as1200metres and equally deduced the width of side-lobes in the received radiation pattern, whose minimization, using the 7th order Chebyshev Polynomials, minimized interference effects in the signal propagation path. Comparison of the Isolation models showed that the Traditional Antenna Isolation Model used by most Researchers, yield isolation loss of less than 75dB at the far-field distance of the interfered with CDMA 2000 1X Base Station (BS) antenna Receiver footprint with dropped calls of 42 and Call Drop Rate (CDR) of 13.33%; which was above the 13% Standard (3GPP TR, 2002). The use of the Proposed Isolation Model has the advantage of isolation improvement at no extra cost. Isolation loss of more than 99dB was attained at the far-field distance of the interfered with BS antenna Receiver and at the footprint, dropped calls of 31 and CDR of 9.84% were recorded.