The RCMP is known to have a network of repeaters across the country in the UHF range, a mobile UHF trunking system, as well as caches of UHF portables available for special events and such. It's likely for use on these frequencies, P25 encrypted.
It's my understanding that there's 30-40 UHF frequencies set aide for their use nationwide.
PPSTN radios are VHF only. I suspect that the UHF antenna is for an RPS mobile radio as RPS CTS units have RCMP PPSTN radios in addition to their UHF radios.
Probably not the case with the RCMP, but a door popper/hot car systems for K9 units have those UHF antennas.
Like a dog handler outside the car can open the side door and their dog can run out and bite something for them. Or, let them out of a hot car. (probably less likely than I think because cops leave things running AC on almost always). Some cars have a little switch that lets them take their keys out and it stays running until the brake is pressed and then it shuts off.
Probably not the case with the RCMP, but a door popper/hot car systems for K9 units have those UHF antennas.
Like a dog handler outside the car can open the side door and their dog can run out and bite something for them. Or, let them out of a hot car. (probably less likely than I think because cops leave things running AC on almost always). Some cars have a little switch that lets them take their keys out and it stays running until the brake is pressed and then it shuts off.