US 9,319,952 B2 · Apparatus and methods for synchronization recovery in a hybrid network

Abstract

Methods and apparatus for synchronizing operational state during hybrid network operation. In one embodiment, the various access technologies that makeup the hybrid network not fully synchronized. Thus, a wireless device operating in a mixed mode must be capable of managing synchronization across multiple access technologies. The wireless device is configured to estimate an expected “tune-away” period when disengaging with a one access technology to address events (for example, link maintenance, calls, data, and the like) or perform monitoring on a second access technology. The estimate is then used by the device to adjust its operational parameters on the technology from which it is tuning away. This ensures smooth switching away from and back to the various network technologies.

Claims20

Dependent claims

A method by a (UE) client device during a hybrid network operation, where hybrid network operation of the UE client device is characterized by intermittent switching between a first long term evolution (LTE) network and a second Code Division Multiple Access 1× (CDMA 1×) network, the method comprising:

by the UE client device:
identifying one or more tune away events that are likely to adversely impact operation of the UE client device, where during the one or more tune away events the UE client device tunes away from the first LTE network;
estimating a duration of the one or more tune away events;
determining an adjustment to a Timing Advance (TA) timer maintained at the UE client device based on the estimated duration of the one or more tune away events, wherein the adjustment is determined to support triggering a loss of state synchronization;
after completion of the one or more tune away events, adjusting the TA timer according to the determined adjustment;
identifying the loss of state synchronization subsequent to the adjusting and based on an expiration of the TA timer;
and
sending a Random Access Channel (RACH) sequence to the LTE network subsequent to identifying the loss of state synchronization.

5 more elements

A wireless device configurable for hybrid network operation in a first network according to a first access technology and in a second network according to a second access technology, the wireless device comprising:

a first interface configured to maintain an operative link via the first access technology;
a second interface configured to maintain an operative link via the second access technology;
and
logic coupled to the first and second interfaces and configured to cause the wireless device to:
based on an event associated with the first access technology, predict an occurrence of a tune away period associated with the second access technology;
analyze the event to determine a length of the tune away period;
based on the length of the tune away period, determine an adjustment to a Timing Advance (TA) timer maintained at the wireless device, wherein the adjustment is determined to support triggering a loss of state synchronization;
adjust the TA timer according to the determined adjustment after a completion of a tune away event;
identify the loss of state synchronization, subsequent to the adjusting and based on an expiration of the TA timer;
and
send a Random Access Channel (RACH) sequence to the second network subsequent to identifying the loss of state synchronization.

8 more elements

A non-transitory computer-readable apparatus configured to store one or more computer processes thereon, the one or more computer processes comprising a plurality of instructions that, when executed by a processor, cause a user equipment (UE) client device to:

identify one or more tune away events that are likely to adversely impact operation of the UE client device, wherein during the one or more tune away events the UE client device tunes away from a first network to a second network;
estimate a duration of the one or more tune away events;
determine an adjustment to a Timing Advance (TA) timer maintained at the UE client device based at least in part on the estimated duration of the one or more tune away events, wherein the adjustment is selected to support triggering a loss of state synchronization;
after completion of the one or more tune away events, adjust the TA timer according to the determined adjustment;
identify the loss of state synchronization subsequent to the adjusting and based on an expiration of the TA timer;
and
send a Random Access Channel (RACH) sequence to the LTE network subsequent to identification of the loss of state synchronization.

4 more elements

Dependencies are inferred from the claim text.

Apparatus and methods for synchronization recovery in a hybrid network

Life of this patent

Apparatus and methods for synchronization recovery in a hybrid network

Life of this patent

Abstract

Claims20