wireless, frequency vs range?
Say for example I'm designing a wireless product, such as a new type of cell phone or computer. And it's supposed to be a point to point system, instead of going through the corporate cell towers or cable modems like the internet and cell phone networks now. With that there is the concern of range, will my device be able to reach others from a decent distance?
I know there are two main unlicensed bands that are commonly used, the 900 MHz one and the 2.4 GHz. I've heard there is such a relationship that the lesser the frequency, the greater the range. Is this true? Consider a suburban area for this kind of thing. And also, I've heard that 900 MHz isn't much used outside the US, is this true? Because it's not allowed in many countries?