i just got off the phone with sprint and they told me that samsung pushed an update on friday to fix a delay in receiving text messages which has borked the internal antenna. that would explain why i only started having problems yesterday.... sprint will give you a ticket number and they will fix your phone for free at a store.
call up and get it fixed.
its only going to get worse!
Macrodriod Device Automation
ODEX your Rom
Device 1: .: Note 3 T-Mobile :.
Rom: .: Odexed Cyanogen Mod 11 :.
Recovery:[/COLOR] .: TWRP 22.214.171.124 :.
Device 2: .: SGS4 T-Mobile :.
Rom:.: Cyanogen Mod 11 :.
Kernel: .: KT747 :.
Recovery: .: TWRP 126.96.36.199 :.