The advantage of the old Ademco 5800 format was strong signal propagation and wide availability of sensors from Honeywell as well as the aftermarket (Resolution Products and others). They are UL listed and that listing requires the system to be able to detect and report outside jamming attempts. While it is theoretically possible to jam a sensor the attempt would be detected by the system and can act on it accordingly. Finally, a good installation would also layer in hardwired sensors so even if a wireless sensor were to be successfully jammed and entry made another (hardwired) sensor would detect the intruder.
That said, if "spread spectrum" capability is an important consideration for you, perhaps you should consider an Elk M1 system (Gold or EZ8) with Elk's "Two-Way Wireless" sensors. Aside from the obvious features of frequency hopping, encryption and 2-way transmission acknowledgement, the fact that it is proprietary to a relatively small vendor means it's less likely that the technical details have been flushed out by hackers and compromised.
Per the Elk website:
In addition to encrypting the signal transmissions, ELK utilizes frequency-hopping across a broad spectrum in the 900 MHz band. The system automatically scans and hops across 25 frequency channels, making it "virtually impossible" for intruders to lock onto the signal and thereby hack the system.
That said, if "spread spectrum" capability is an important consideration for you, perhaps you should consider an Elk M1 system (Gold or EZ8) with Elk's "Two-Way Wireless" sensors. Aside from the obvious features of frequency hopping, encryption and 2-way transmission acknowledgement, the fact that it is proprietary to a relatively small vendor means it's less likely that the technical details have been flushed out by hackers and compromised.
Per the Elk website:
In addition to encrypting the signal transmissions, ELK utilizes frequency-hopping across a broad spectrum in the 900 MHz band. The system automatically scans and hops across 25 frequency channels, making it "virtually impossible" for intruders to lock onto the signal and thereby hack the system.