Ms Office Tune Up

Apr 23

Okumura Hata GSM Link Budget System in Microsoft Excel

Cellular system planning is either coverage of capacity driven. Initially, an operator attempts to cover the service area as good as possible with only a limited number of base stations. His main concern is that the signal-to-noise ratio is sufficient at each location. The link budget is a kind of “balance sheet” to select the system parameters Interference is not yet limiting the system performance.

In a latter phase when more subscribers are using the system, the operator typically attempts to improve capacity by adding more base stations. The grid of base stations becomes denser and signal-to-noise ratio is no longer limiting the performance. Co-channel and adjacent channel interference become more of concern.

This template allows you to calculate the link budget for a the uplink in a GSM (or GSM-like) network. It’s a simplified GSM link budget system that is developed using Okumura Hata model.

Â Okumura Hata GSM Link Budget System in Microsoft Excel

The so-called Okumura-Hata curve is an approximation of radio wave propagation characteristics based on aggregated data obtained in actual tests of propagation characteristics between a base station and mobile stations in various areas, such as open land, suburbs, a medium city, and a large city. The electric field intensity for each area is calculated by applying a correction value to the standard field intensity, which is that of an urban area in quasi-smooth terrain.

Although the testing was carried out some time ago, the results are still being used as important basic data for radio wave propagation characteristics. However, since the method of classifying the areas such as urban and suburban is not always clear, differences in the calculated values may arise according to which type of area the local system is assumed to be located. In addition, the data for propagation characteristics is for when the base station antenna is higher than the surrounding buildings, and there are slight differences from the environment of use of specific low power radio equipment. Therefore prudence is required in judging the validity of the calculation result.