Support of multiple modulation levels for a cellular packet control channel
First Claim
1. In a mobile communications system having an air interface supporting a low-level modulation packet control channel and packet traffic channel and further supporting a high-level modulation packet control channel and packet traffic channel, a method for packet channel selection by an idle mobile station, comprising the steps of:
- attempting to access the high-level modulation packet control channel;
if the access is successful, measuring communications quality on the high-level modulation packet control channel;
determining if the measured communications quality is sufficient for data communications; and
if so, assigning the high-level modulation packet control channel and the high level modulation packet traffic channel as the selected packet channels for the mobile station.
1 Assignment
0 Petitions
Accused Products
Abstract
A D-AMPS+ cellular communications air interface is presented wherein a packet data control channel and packet data traffic channel is supported in addition to the conventional digital control channel and digital traffic channel. In particular, the packet data control channel and packet data traffic channel support multiple modulation level operation (high versus low). Procedures are provided for mobile station selection, as well as re-selection, of either the high or low-level modulation for the packet channels. Procedures are further provided for facilitating a fall-forward to the high-level modulation packet data control channel, or a fall-backward to the low-level modulation packet data control channel with respect to both uplink and downlink packet data communications.
71 Citations
24 Claims
-
1. In a mobile communications system having an air interface supporting a low-level modulation packet control channel and packet traffic channel and further supporting a high-level modulation packet control channel and packet traffic channel, a method for packet channel selection by an idle mobile station, comprising the steps of:
-
attempting to access the high-level modulation packet control channel; if the access is successful, measuring communications quality on the high-level modulation packet control channel; determining if the measured communications quality is sufficient for data communications; and if so, assigning the high-level modulation packet control channel and the high level modulation packet traffic channel as the selected packet channels for the mobile station. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. In a mobile communications system having an air interface supporting a low-level modulation packet control channel and a high-level modulation packet control channel, a method for downlink packet control channel data communications fall-forward, comprising the steps of:
-
downlink sending of a plurality of communications frames over the low-level modulation packet control channel; responsive to a correct reception of the sent plurality of communications frames, incrementing a counter; comparing the counter to a threshold; downlink sending of a command to switch to the high-level modulation packet control channel if the counter meets or exceeds the threshold; switching to the high-level modulation packet control channel; and downlink sending of a plurality of communications frames over the high-level modulation packet control channel. - View Dependent Claims (8, 9, 10, 11)
-
-
12. In a mobile communications system having an air interface supporting a low-level modulation packet control channel and a high-level modulation packet control channel, a method for uplink packet control channel data communications fall-forward, comprising the steps of:
-
uplink sending of a communications frame over the low-level modulation packet control channel; responsive to a correct reception of the sent communications frame, incrementing a counter; comparing the counter to a threshold; switching to the high-level modulation packet control channel if the counter meets or exceeds the threshold; and uplink sending of a communications frame over the high-level modulation packet control channel. - View Dependent Claims (13, 14, 15, 16)
-
-
17. In a mobile communications system having an air interface supporting a low-level modulation packet control channel and a high-level modulation packet control channel, a method for downlink packet control channel data communications fall-backward, comprising the steps of:
-
downlink sending of a plurality of communications frames over the high-level modulation packet control channel; responsive to an incorrect reception of the sent plurality of communications frames, incrementing a counter; comparing the counter to a threshold; switching for transmission to the low-level modulation packet control channel if the counter meets or exceeds the threshold; and downlink sending of a plurality of communications frames over the low-level modulation packet control channel. - View Dependent Claims (18, 19, 20, 21)
-
-
22. In a mobile communications system having an air interface supporting a low-level modulation packet control channel and a high-level modulation packet control channel, a method for uplink packet control channel data communications fall-backward, comprising the steps of:
-
uplink sending of a communications frame over the high-level modulation packet control channel; responsive to a incorrect reception of the sent communications frame, incrementing a counter; comparing the counter to a threshold; switching to the low-level modulation packet control channel if the counter meets or exceeds the threshold; and uplink sending of a communications frame over the low-level modulation packet control channel. - View Dependent Claims (23, 24)
-
Specification