Modified accelerating lens as a means of increasing the throughput, range and noise immunity of IEEE 802.11 systems

The paper addresses new results of research on the use of an accelerating lens to increase throughput, range and noise immunity of exchange in a certain priority direction in the system of wireless access of IEEE 802.11 standard. Compared with previous works, efforts have been focused on solving these problems as applied to the MIMO systems, in which a problem emerges to choose an all-purpose lens profile to ensure the same conditions for increasing directional properties of the two (or more) antennas. This has required the development of a methodology for calculating the lens profile with allowance for two (or more) phase centers. The second factor that distinguishes the presented results is related to the analysis of the range properties of the lens and working out recommendations on the use of it in the frequency range used for servicing users in this standard. It seems rational to calculate lenses for a maximum wavelength that allows providing its relative transparency (and, consequently, certain efficiency) for shorter wavelengths range used, but with worse directional characteristics.

1. Previous Developments

Unlike the previous work of the authors [1], which addressed the issue of increasing the access range for an individual subscriber of the IEEE 802.11 system at the cost of using a metal-lamellar cylindrical lens with a single-channel equipment wireless access point. The paper examines the possibility of using the aforementioned type of lenses for the MIMO systems with two (or more) antennas. This raises the problem of choosing the parameters of the lens, which would allow increasing characteristics of information accessibility in both channels, whose antennas are cross-separated and in absolute sense, cannot be located in the focus of the lens. Solution of this problem can be achieved in two ways: •

By the increase in the lens focal distance so that to ensure (with a margin) meeting the terms of location of the irradiated lens surface in the far field of the system of two emitters.

•

By modification of the lens profile so that to satisfy (as a first approximation) the requirement of the same positions of radiation patterns (RP) formed when using the emitters shifted both to the left and to the right from the lens phase center.