What is the radio polygon?

Answer 1

If you mean the Radio Polygon used by mobile phone providers, its a coverage area that is served by a group of cells all of which are connected to a specific piece of equipment called an RNC (radio network controller).

If you travel whilst calling you are moved automatically from cell to cell - meaning that your phone connects to a new radio transmission station (called a base station) automatically. When you move between cells that are on different RNC there is additional processing required - especially if the new connection is with a different operator - or roaming When a company starts to develop a network in a given area it uses the positions and number of base stations to decide how many RNC are needed (they are very expensive - $2m ). When you add all of the base station coverage areas together you don't get a nice border because the base stations aren't located at regular intervals, they are dotted all over the map. Because its hard to manage this conceptually the designers draw a straight line around an area of the map that is served by a number of base stations and designates this 'polygon' to be controlled by an RNC.

An obvious option would be to draw a simple grid over the are of coverage and assign RNC to each square but this would waste a lot of capacity in the edges whilst overloading the ones near the middle. The trick is to get enough coverage for all you subscribers in a given area using the fewest base stations and therefore the fewest RNC.