Method and apparatus for handling measurement gaps in wireless networks

Abstract

In a wireless communication system, user equipment (UE) has autonomy provided by one or more set of rules to handle processing during a measurement gap. UE can ignore or use only a portion of the whole measurement gap if not needed. Thereby, an urgent need for remaining tuned to source carrier frequency can be supported, such as utilizing Random Access Channel (RACH) procedure. UE can also choose to tune to a target carrier frequency supporting timely handovers. Depending on the type of processing required (download shared channel (DL-SCH, UL-SCH, TTI bundling, RACH or SR), the UE may store requests and process the measurements during the gap or ignore the gap measurement as if there were no gaps.

1 . A method for utilizing a measurement gap, comprising:
 wirelessly communicating on a source carrier frequency;   receiving an assignment for a measurement gap on the source carrier frequency;   independently determining to remain tuned to the source carrier frequency during at least a portion of the measurement gap; and   selectively tuning between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       2 . The method of  claim 1 , further comprising:
 independently determining to tune away from the source frequency later than the beginning of the measurement gap; and   tuning from the source to the target carrier frequency after a start time assigned to the measurement gap.   
   
   
       3 . The method of  claim 1 , further comprising:
 independently determining to tune back to the source frequency earlier than the end of the measurement gap; and   tuning from the target to the source carrier frequency before a stop time assigned to the measurement gap.   
   
   
       4 . The method of  claim 3 , further comprising:
 independently determining to depart tune away from the source frequency later than the beginning of the measurement gap; and   tuning from the source to the target carrier frequency after a start time assigned to the measurement gap.   
   
   
       5 . The method of  claim 1 , further comprising:
 independently determining to cancel departure from the source frequency during the measurement gap; and   remaining tuned to the source carrier frequency during the measurement gap.   
   
   
       6 . The method of  claim 1 , further comprising:
 receiving and processing a downlink transmission from a base station operating on the source frequency during an independently determined portion of the measurement gap.   
   
   
       7 . The method of  claim 6 , wherein the downlink transmission is PDCCH (physical downlink control channel) or PDSCH (physical downlink shared channel). 
   
   
       8 . The method of  claim 1 , further comprising:
 performing an uplink shared channel (UL-SCH) transmission that is scheduled to occur during the measurement gap;   
   
   
       9 . The method of  claim 1 , further comprising:
 receiving Hybrid Automatic-Repeat-Request (HARQ) acknowledgement (ACK/NAK) when HARQ feedback collides with a measurement gap.   
   
   
       10 . The method of  claim 1 , further comprising performing a PRACH transmission that collides with a measurement gap. 
   
   
       11 . The method of  10 , further comprising:
 determining whether to perform PRACH based on potential collision of subsequent transmissions related to the Random Access Procedure with a measurement gap.   
   
   
       12 . The method of  claim 1 , further comprising performing transmission of a selected one of Scheduling Request, Sounding Reference Signal and CQI (channel quality indicator) report, when it collides with a measurement gap. 
   
   
       13 . At least one processor for utilizing a measurement gap, comprising:
 a first module for wirelessly communicating on a source carrier frequency;   a second module for receiving an assignment for a measurement gap on the source carrier frequency;   a third module for independently determining to remain tuned to the source carrier frequency during at least a portion of the measurement gap; and   a fourth module for selectively tuning between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       14 . A computer program product for utilizing a measurement gap, comprising:
 a computer-readable storage medium comprising,
 a first set of codes for causing a computer to wirelessly communicate on a source carrier frequency; 
 a second set of codes for causing the computer to receive an assignment for a measurement gap on the source carrier frequency; 
 a third of codes for causing a computer to independently determine to remain tuned to the source carrier frequency during at least a portion of the measurement gap; and 
 a fourth of codes for causing a computer to selectively tune between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination. 
   
   
   
       15 . An apparatus for utilizing a measurement gap, comprising:
 means for wirelessly communicating on a source carrier frequency;   means for receiving an assignment for a measurement gap on the source carrier frequency;   means for independently determining to remain tuned to the source carrier frequency during at least a portion of the measurement gap; and   means for selectively tuning between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       16 . An apparatus for utilizing a measurement gap, comprising:
 a transmitter for wirelessly communicating on a source carrier frequency;   a receiver for receiving an assignment for a measurement gap on the source carrier frequency; and   a computing platform for independently determining to remain tuned to the source carrier frequency during at least a portion of the measurement gap,   wherein the computing platform is further for selectively tuning the receiver between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       17 . The apparatus of  claim 16 ,
 wherein the computing platform is further for independently determining to tune away from the source frequency later than the beginning of the measurement gap; and   the computing platform is further for tuning the receiver from the source to the target carrier frequency after a start time assigned to the measurement gap.   
   
   
       18 . The apparatus of  claim 16 ,
 wherein the computing platform is further for independently determining to tune back to the source frequency earlier than the end of the measurement gap; and   the computing platform is further for tuning the receiver from the target to the source carrier frequency before a stop time assigned to the measurement gap.   
   
   
       19 . The apparatus of  claim 18 ,
 wherein the computing platform is further for independently determining to depart tune away from the source frequency later than the beginning of the measurement gap; and   the computing platform is further for tuning the receiver from the source to the target carrier frequency after a start time assigned to the measurement gap.   
   
   
       20 . The apparatus of  claim 16 ,
 wherein the computing platform is further for independently determining to cancel departure from the source frequency during the measurement gap; and   wherein the computing platform is further for remaining tuned to the source carrier frequency during the measurement gap.   
   
   
       21 . The apparatus of  claim 16 , wherein the computing platform is further for receiving and processing a downlink transmission from a base station operating on the source frequency during an independently determined portion of the measurement gap. 
   
   
       22 . The apparatus of  claim 21 , wherein the downlink transmission is PDCCH (physical downlink control channel) or PDSCH (physical downlink shared channel). 
   
   
       23 . The apparatus of  claim 16 , wherein the transmitter is further for performing an uplink shared channel (UL-SCH) transmission that is scheduled to occur during the measurement gap; 
   
   
       24 . The apparatus of  claim 16 , wherein the receiver is further for receiving Hybrid Automatic-Repeat-Request (HARQ) acknowledgement (ACK/NAK) when HARQ feedback collides with a measurement gap. 
   
   
       25 . The apparatus of  claim 16 , wherein the transmitter is further for performing a PRACH transmission that collides with a measurement gap. 
   
   
       26 . The apparatus of  25 , wherein the computing platform is further for determining whether to perform PRACH based on potential collision of subsequent transmissions related to the Random Access Procedure with a measurement gap. 
   
   
       27 . The apparatus of  claim 16 , wherein the transmitter is further for performing transmission of a selected one of Scheduling Request, Sounding Reference Signal and CQI (channel quality indicator) report, when it collides with a measurement gap. 
   
   
       28 . A method for assigning a measurement gap, comprising:
 wirelessly communicating on a source carrier frequency;   transmitting an assignment for a measurement gap on the source carrier frequency; and   facilitating user equipment to independently determine to remain tuned to the source carrier frequency during at least a portion of the measurement gap and to selectively tune between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       29 . The method of  claim 28 , wherein user equipment can independently determine to tune away during a beginning portion, a mid portion, an ending portion, an entire portion, or to not tune away at all. 
   
   
       30 . The method of  claim 28 , further comprising transmitting a downlink transmission during the measurement gap in expectation that user equipment has remained tuned to the source frequency. 
   
   
       31 . The method of  claim 30 , wherein the downlink transmission is PDCCH (physical downlink control channel) or PDSCH (physical downlink shared channel). 
   
   
       32 . The method of  claim 28 , further comprising receiving an uplink shared channel (UL-SCH) transmission from user equipment that is scheduled to occur during the measurement gap; 
   
   
       33 . The method of  claim 28 , further comprising:
 transmitting Hybrid Automatic-Repeat-Request (HARQ) acknowledgement (ACK/NAK) when HARQ feedback collides with a measurement gap.   
   
   
       34 . The method of  claim 28 , further comprising receiving a PRACH transmission from user equipment that collides with a measurement gap. 
   
   
       35 . The method of  claim 28 , further comprising receiving transmission from user equipment of a selected one of Scheduling Request, Sounding Reference Signal and CQI (channel quality indicator) report, when it collides with a measurement gap. 
   
   
       36 . At least one processor for assigning a measurement gap, comprising:
 a first module for wirelessly communicating on a source carrier frequency;   a second module for transmitting an assignment for a measurement gap on the source carrier frequency; and   a third module for facilitating user equipment to independently determine to remain tuned to the source carrier frequency during at least a portion of the measurement gap and to selectively tune between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       37 . A computer program product for assigning a measurement gap, comprising:
 a computer-readable storage medium comprising,
 a first set of codes for causing a computer to wirelessly communicate on a source carrier frequency; 
 a two set of codes for causing the computer to transmit an assignment for a measurement gap on the source carrier frequency; and 
 a third of codes for causing a computer to facilitate user equipment to independently determine to remain tuned to the source carrier frequency during at least a portion of the measurement gap, and to selectively tune between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination. 
   
   
   
       38 . An apparatus for assigning a measurement gap, comprising:
 means for wirelessly communicating on a source carrier frequency;   means for transmitting an assignment for a measurement gap on the source carrier frequency; and   means for facilitating user equipment to independently determine to remain tuned to the source carrier frequency during at least a portion of the measurement gap, and to selectively tune between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with the independent determination.   
   
   
       39 . An apparatus for assigning a measurement gap, comprising:
 a receiver for wirelessly communicating on a source carrier frequency;   a transmitter for transmitting an assignment for a measurement gap on the source carrier frequency; and   a computing platform for independently determining to remain tuned to the source carrier frequency during at least a portion of the measurement gap,   wherein the user equipment selectively tunes its transmitter between the source carrier frequency and a target carrier frequency during the measurement gap in accordance with its independent determination.   
   
   
       40 . The apparatus of  claim 39 , wherein user equipment can independently determine to tune away during a beginning portion, a mid portion, an ending portion, an entire portion, or to not tune away at all. 
   
   
       41 . The apparatus of  claim 39 , wherein the transmitter is further for transmitting a downlink transmission during the measurement gap in expectation that user equipment has remained tuned to the source frequency. 
   
   
       42 . The apparatus of  claim 41 , wherein the downlink transmission is PDCCH (physical downlink control channel) or PDSCH (physical downlink shared channel). 
   
   
       43 . The apparatus of  claim 39 , wherein the receiver is further for receiving an uplink shared channel (UL-SCH) transmission from user equipment that is scheduled to occur during the measurement gap; 
   
   
       44 . The apparatus of  claim 39 , wherein the transmitter is further for transmitting Hybrid Automatic-Repeat-Request (HARQ) acknowledgement (ACK/NAK) when HARQ feedback collides with a measurement gap. 
   
   
       45 . The apparatus of  claim 39 , wherein the receiver is further for receiving a PRACH transmission from user equipment that collides with a measurement gap. 
   
   
       46 . The apparatus of  claim 39 , wherein the receiver is further for receiving transmission from user equipment of a selected one of Scheduling Request, Sounding Reference Signal and CQI (channel quality indicator) report, when it collides with a measurement gap.