95 Honda Passport factory alarm specs?

I have a '95 Honda Passport with a factory (genuine Honda accessory.... they did not come with factory installed security).  Neither the installation manual nor the user's manual mention the frequency used.  There is no mention of the frequency on the control unit or either of the remotes.  (Honda cannot or will not supply much information). 

1.  Does anyone know the frequency (or approximate frequency if it is some kind of secret)?

2.  In my LIMITED radio frequency experience I learned that there are 1/4 wave, 1/2 wave, and full length antennas.  I am interested in increasing my range a bit.  Currently it is good for my needs (100+ feet), but that is after I moved the antenna a few inches.  Prior to moving it my range varied from 10 - 25 feet.  I would like to avoid this type of problem by extending or relocating the antenna (presumably some type of coax leading to an antenna located elsewhere in (or on) the vehicle.  Can this antenna (just a single unshielded wire be lengthened?  Can this antenna be replaced with a grounded coax leading to an antenna?

TIA

Also......

3.  Does anyone know what manufacturer Honda used for this system?  The only reference is a "supplier part number" on the control unit.  If you don't know who the manufacturer is perhaps the supplier part number might mean something to you.  The supplier part number is: 202-3156

TIA