SEATTLE--(BUSINESS WIRE)--Motorola Solutions (NYSE: MSI) has begun upgrading the Puget Sound Emergency Radio Network (PSERN) infrastructure in a $112 million contract to bring King County first responders the latest ASTRO® 25 digital radio technology that will enhance public safety every year as the project progresses. The 55-month upgrade leverages new transmission towers to elevate the system’s reliability to help protect the fast-growing county’s more than 2 million residents. King County vo