POINT TO POINT

Point To Point in wireless means almost exactly what the words say.  For normal wireless transmission and reception, the antennas used transmit in a number of directions such that they can communicate with other wireless units that may be in many different locations.  For point to point wireless operation, the opposite is true.  The only transmission and reception cared about is one in a very specific direction.  If you think of a point to point wireless system as being similar to a single wire cable, you might be the idea.  A single wired cable can go only to one other place - unless it is spliced or connected to.  Likewise a point to point wireless transmission transmits and receives from only one location.  Point to point is the wireless equivalent therefore of a single cable.

Point to point transmission often uses dish antennas, which are also called parabolic antennas for transmission.  What these antennas do is concentrate all of the transmitted energy and all of the receive energy in a single direction.  These antennas may also be considered high gain antennas since they do concentrate all of their energy in a single direction.  But while these antennas are high gain and therefore can transmit and receive long distances, the negative is that they must be exactly pointed at the source we are transmitting to and receiving from.  This does require some care in aiming the antenna.

One example of point to point transmission very common nowadays is in satellite TV.  The satellite's orbit ensures that it is always in exactly the same place in the sky.  The location of the house receiving the signal also remains the same.  Therefore, one can use point to point antenna systems and use a dish antenna to get the best reception from the satellite.  But as stated before, the dish antenna must be pointed in the right direction - since it is a very directional high gain antenna.

Note that point to point transmission is also sometimes called microwave transmission - due to the frequencies used for point to point at one time.