Any recommendations for smoke detectors with wireless remote alarms?
I have First Alert Onelink in my home. It has a voice notification that indicates the location of the module activated to all other modules. (I have 4 in my home) There are hard-wired and battery powered units. They also use a photoelectric smoke sensor that reduces nuisance alarms from normal smoke or steam.

I personally don't know about the barn issue or the wireless range; but they have quite a few options among the models on the First Alert site.