The pseudolite/satelite arguement comes down to line of sight. Low altitude fixed broadcasting stations -vs- satelites.
1 - TV and GPS signals are not light. They go straight.
So do signals from pseudolites.
b. If pseudolites transmit as far as FM radio stations can (100 miles -ish) we still need 18000 of them to cover the states.
That seems a reasonable number.
c. If all these communications are coming in laterally or say within 10 deg of the horizon; Why are satelite dishes pointed at much higher angles?
Pseudolites will be placed at high points. It makes sense. The signal will travel much further than expected because the earth is flat. Also, to receive signals from stratellites.
d. Why is it that the only time the satelite radio in my car cant get signal is when I am directly under something? never next to anything? I get signal in a canyon, or driving arround in a city, but not under a bridge or in the covered drive through at a bank?
This makes perfect sense with stratellites and pseudolites too. If you are in a canyon, there is quite a large chance that a pseudolite will be transmitting a signal from somewhere past one end of the canyon. If you are under a bridge, since most pseudolites are on high places, you will not receive a signal.