Inventor
WILLARD DAVID F
US28 patents
Patents
28 patentsUS5311516AMay 10, 1994
Paging system using message fragmentation to redistribute traffic
MOTOROLA INC380 citations99
US4803487AFeb 7, 1989
Portable communications receiver with separate information presentation means
MOTOROLA INC255 citations99
US4914649AApr 3, 1990
Multiple frequency message system
MOTOROLA INC125 citations98
US5325088AJun 28, 1994
Synchronous selective signalling system
MOTOROLA INC84 citations96
US5208833AMay 4, 1993
Multi-level symbol synchronizer
MOTOROLA INC96 citations96
US5206855AApr 27, 1993
Multiple frequency message system
MOTOROLA INC106 citations96
US5089813AFeb 18, 1992
Method of super battery saving in a selective call receiver
MOTOROLA INC85 citations96
US4803703AFeb 7, 1989
Apparatus and method for fine synchronization of a communication receiver
MOTOROLA INC109 citations96
US5168493ADec 1, 1992
Time division multiplexed selective call system
MOTOROLA INC57 citations95
US4873520AOct 10, 1989
Paging receiver for storing digitized voice messages
MOTOROLA INC83 citations94
US5555183ASep 10, 1996
Method and apparatus for synchronizing to a synchronous selective call signal
MOTOROLA INC40 citations93
US5455579AOct 3, 1995
Digitized stored voice paging receiver
MOTOROLA INC73 citations93
US4965569AOct 23, 1990
Digitized stored voice paging receiver
MOTOROLA INC92 citations93
US4412217AOct 25, 1983
Pager with visible display indicating status of memory
MOTOROLA INC72 citations93
US5956640ASep 21, 1999
Messaging system providing flexible roaming and method therefor
MOTOROLA INC37 citations92
US5610919AMar 11, 1997
Network identification information placement architecture for messaging system having roaming capability
MOTOROLA INC39 citations92
US5600312AFeb 4, 1997
Messaging system and method having roaming capability and controlled group messaging
MOTOROLA INC43 citations92
US5493282AFeb 20, 1996
Addressing method for conserving power in distributed information receivers
MOTOROLA INC21 citations92
US5475863ADec 12, 1995
Method and apparatus for delivering messages to portable communication units in a radio communication system
MOTOROLA INC87 citations92
US5371737ADec 6, 1994
Selective call receiver for receiving a multiphase multiplexed signal
MOTOROLA INC20 citations91
US5546394AAug 13, 1996
Message fragmenting in a time diversity radio system
MOTOROLA INC28 citations90
US5635914AJun 3, 1997
Method and apparatus for dynamic group calling in a selective call system
MOTOROLA INC45 citations89
US5625351AApr 29, 1997
Messaging system having roaming capability
MOTOROLA INC24 citations89
US4385295AMay 24, 1983
Pager with visible display indicating unread messages
MOTOROLA INC43 citations89
US5051993ASep 24, 1991
Mixed modulation level communication system
MOTOROLA INC13 citations74
US6229794B1May 8, 2001
Selective call device and method for monitoring at least two communication systems
MOTOROLA INC6 citations63
US6101370AAug 8, 2000
Method and apparatus used in a simulcast radio communication system for providing improved local time
MOTOROLA INC6 citations63
US4151367AApr 24, 1979
Data sync acquisition in an asynchronous binary address decoder
MOTOROLA INC2 citations54