TacOps, page 278 states "...the Bloodhound can detect hidden units with stealth or sneak ability, including Battle Armor units with Stealth Armor, Mimetic Armor, and ECM..."
What's not clear is if a Bloodhound can detect a hidden Battle Armor unit with both an ECM Suite and Stealth (or Mimetic) armor. A similar situation would exist for Battle Armor with either of those types of armor hidden within the ECM field of another unit. If Stealth and Mimetic armor could be simultaneously mounted on Battle Armor, the rule as written would be clear.