US 6,606,309 B1 · Time-multiplexed short message acknowledgement systems and methods

Abstract

Access requests are communicated from a plurality of radiotelephones to a central station over a random access channel carrier frequency band during a first RACH message time window. Short message acknowledgements are communicated from the plurality of radiotelephones to the central station over the random access channel carrier frequency band during a second RACH message time window, in response to short messages communicated from the central station to the plurality of radiotelephones. Preferably, the first RACH message time window includes a first set of TDMA time slots in a group of TDMA control channel multiframes, and the second RACH message time window includes a second set of TDMA time slots in the group of TDMA control channel multiframes, thereby forming a RACH multiframe. Preferably, the first and second RACH message time windows are separated by a guard time. A radiotelephone communications signal representing a short message acknowledgement encoded according to a predetermined short message code, preferably previously communicated to a radiotelephone in a short message from the central station, may be transmitted from the radiotelephone. The radiotelephone communications signal is received at the central station and decoded according to the predetermined short message code to thereby recover a short message acknowledgement. The plurality of radiotelephones may be arranged into paging groups, each having a unique short message code assigned thereto, and a limited number of short message including the unique short message code may be communicated during a given RACH multiframe.

Claims28

Dependent claims

A method of communicating access requests and short message acknowledgments in a radiotelephone communications system including a central station and a plurality of radiotelephones communicating over a plurality of carrier frequency bands, the radiotelephone communications system including a short message service (SMS) for communicating short messages from the central station to the plurality of radiotelephones, the method comprising the steps:

communicating access requests from the plurality of radiotelephones to the central station over a random access channel carrier (RACH) frequency band during a first RACH message time window, the access requests representing requests for access to the radiotelephone system such that communication of access requests from the plurality of radiotelephones on the RACH carrier frequency band is constrained to occur during the first RACH message time window;
and
communicating short message acknowledgements from the plurality of radiotelephones to the central station over the RACH carrier frequency band during a second RACH message time window such that communication of short message acknowledgements from the plurality of radiotelephones on the RACH carrier frequency band is constrained to occur during the second RACH message time window.

A method of communicating access requests and short message acknowledgements in a time-division multiple access (TDMA) radiotelephone communications system, the TDMA radiotelephone communications system communicating between a central station and a plurality of radiotelephones over a plurality of carrier frequency bands, the plurality of radiotelephones communicating access requests to the central station over a random access channel (RACH) carrier frequency band, the radiotelephone communications system including a short message service (SMS) which communicates alphanumeric messages from the central station to the plurality of radiotelephones and communicates short message acknowledgements from the plurality of radiotelephones to the central station over the RACH carrier frequency band in response to the short messages, the method comprising the steps of:

time-division-multiplexing the access requests and the short message acknowledgements on the RACH carrier frequency band into a first RACH message time window and a second RACH message time window, respectively such that transmission of access requests on the RACH carrier frequency band is constrained to occur during, the first RACH message time window and transmission of short message acknowledgements on the RACH carrier frequency band is constrained to occur during the second RACH message time window.

A radiotelephone communications system, comprising:

a central station;
a plurality of radiotelephones;
short message communicating means for communicating alphanumeric messages from said central station to the plurality of radiotelephones;
access request communicating means for communicating access requests from the plurality of radiotelephones to the central station over a random access channel (RACH) carrier frequency band during a first RACH message time window, the access requests representing requests for access to the radiotelephone communications system, such that communication of access requests from the plurality of radiotelephones on the RACH carrier frequency band is constrained to occur during the first RACH message time window;
and
short message acknowledgement communicating means, responsive to said short messages, for communicating short message acknowledgements from the plurality of radiotelephones to the central station over the RACH carrier frequency band during a second RACH message time window, such that communication of short message acknowledgements from the plurality of radiotelephones on the RACH carrier frequency band is constrained to occur during the second RACH message time window.

3 more elements

A radiotelephone for communicating with a central station in a radiotelephone communications system, the radiotelephone comprising:

short message receiving means for receiving short messages from the central station;
access request transmitting means for transmitting access requests from the radiotelephone over a random access channel (RACH) carrier frequency band during a first RACH message time window, the access request representing a request for access to the radiotelephone communications system, such that communication of access requests from the radiotelephone on the RACH carrier frequency band is constrained to occur during the first RACH message time window;
and
short message acknowledgement transmitting means, responsive to said short message receiving means, for transmitting short message acknowledgements from the radiotelephone over the (RACH) carrier frequency band during a second RACH message time window, each of said short message acknowledgments being transmitted in response to receipt of a short message from the central station at a radiotelephone such that communication of short message acknowledgements from the radiotelephone on the RACH carrier frequency band is constrained to occur during the second RACH message time window.

1 more element

Dependencies are inferred from the claim text.

Time-multiplexed short message acknowledgement systems and methods

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Time-multiplexed short message acknowledgement systems and methods

Life of this patent

Abstract

Claims28