Mobile station, core network node, base station subsystem, and methods for implementing longer paging cycles in a cellular network
A mobile station, a core network node, a base station subsystem, and various methods are described herein for implementing longer paging cycles (longer Discontinuous Reception (DRX) mode) in a cellular network which has a benefit of reducing the energy consumption of the mobile station's battery.
1. A mobile station configured to implement paging cycles in a cellular network, the mobile station comprising:
at least one processor; and,
at least one memory that stores processor-executable instructions, wherein the at least one processor interfaces with the at least one memory to execute the processor-executable instructions, whereby said mobile station is operable to:
determine whether a serving cell in the cellular network is acceptable to stay camped-on;
based on a result of the determination that the serving cell is acceptable to stay camped-on, perform a first type of synchronizing procedure and attempt to read a radio block received per a first Discontinuous Reception (DRX) mode, wherein the first DRX mode has a longer time period than a legacy second DRX mode; and,
based on a result of the determination that the serving cell is not acceptable to stay camped-on or the mobile station is not able to read the received radio block, perform a second type of synchronizing procedure and attempt to read another radio block, wherein the first type of synchronizing procedure has a shorter duration than the second type of synchronizing procedure.
2. The mobile station of claim 1 , wherein the mobile station is operable to:
when the mobile station is able to read the received radio block, (1) perform an action based on content of the received radio block, (2) schedule a next wake-up time based on the first DRX mode to determine whether the serving cell is acceptable to stay camped-on, and (3) enter sleep mode.
3. The mobile station of claim 1 , wherein the mobile station is operable to:
when the mobile station is able to read the another received radio block, (1) perform an action based on content of the another received radio block, (2) schedule a next wake-up time based on the first DRX mode to determine whether the serving cell is acceptable to stay camped-on, and (3) enter sleep mode; and
when the mobile station is not able to read the another received radio block, (1) schedule a next wake-up time based on the first DRX mode to perform the second type of synchronizing procedure, and (2) enter sleep mode.
4. The mobile station of claim 1 , wherein the mobile station is operable to determine whether the serving cell is acceptable to stay camped-on by:
waking-up a predetermined first time before a start time of a paging cycle based on the first DRX mode;
tuning to a radio frequency of a beacon channel of the serving cell and measuring a Received Signal Strength Indicator (RSSI) of the beacon channel of the serving cell; and
comparing the RSSI to a threshold value, wherein when the RSSI is greater than the threshold value then the result of the determination is that the serving cell is acceptable to stay camped-on, and when the RSSI is less than the threshold value then the result of the determination is that the serving cell is not acceptable to stay camped-on.
5. The mobile station of claim 1 , wherein the first type of synchronizing procedure comprises:
reading a predetermined number of bursts from a received beacon channel of the serving cell;
searching for a Training Sequence Code (TSC) in the read bursts to confirm cell identification of the serving cell;
performing Automatic Frequency Control (AFC) operations and Automatic Time Control (ATC) operations; and
scheduling for reception of the radio block.
6. The mobile station of claim 1 , wherein the mobile station is operable to:
when a result of the determination is that the serving cell is not acceptable to stay camped-on or the mobile station is not able to read the received radio block, wake-up a predetermined second time before a start time of a next paging cycle based on the first DRX mode to perform the second type of synchronizing procedure.
7. The mobile station of claim 1 , wherein the second type of synchronizing procedure comprises:
performing Received Signal Strength Indicator (RSSI) measurement for different frequencies;
performing Frequency Correction Channel (FCCH) search;
performing Synchronization Channel (SCH) search; and
reading Broadcast Control Channel (BCCH) information.
8. The mobile station of claim 1 , wherein when a result of the determination is that the serving cell is not acceptable to stay camped-on then the mobile station is further operable to:
immediately perform the second type of synchronizing procedure;
schedule readings of up to N radio blocks to be received per the legacy second DRX mode, wherein N>1; and
when one of the N radio blocks is successfully read, (1) perform an action based on content of the read one of the N radio blocks, (2) schedule a next wake-up time based on the first DRX mode to determine whether the serving cell is acceptable to stay camped-on, and (3) enter sleep mode; or
when none of the N radio blocks is successfully read, (1) schedule a next wake-up time based on the first DRX mode to perform the second type of synchronizing procedure, and (2) enter sleep mode.
9. The mobile station of claim 1 , wherein the radio block is one of the following: a paging block, a Common Control Channel (CCCH) block, a paging message, or a paging notification.
10. A method in a mobile station for implementing paging cycles in a cellular network, the method comprising:
determining whether a serving cell in the cellular network is acceptable to stay camped-on;
based on a result of the determination that the serving cell is acceptable to stay camped-on, performing a first type of synchronizing procedure and attempting to read a radio block received per a first Discontinuous Reception (DRX) mode, wherein the first DRX mode has a longer time period than a legacy second DRX mode; and,
based on a result of the determination that the serving cell is not acceptable to stay camped-on or the mobile station is not able to read the received radio block, performing a second type of synchronizing procedure and attempting to read another radio block, wherein the first type of synchronizing procedure has a shorter duration than the second type of synchronizing procedure.
11. The method of claim 10 , wherein when the mobile station is able to read the received radio block then (1) performing an action based on content of the received radio block, (2) scheduling a next wake-up time based on the first DRX mode to determine whether the serving cell is acceptable to stay camped-on, and (3) entering sleep mode.
12. The method of claim 10 , wherein:
when the mobile station is able to read the another received radio block, (1) performing an action based on content of the another received radio block, (2) scheduling a next wake-up time based on the first DRX mode to determine whether the serving cell is acceptable to stay camped-on, and (3) entering sleep mode; and
when the mobile station is not able to read the another received radio block, (1) scheduling a next wake-up time based on the first DRX mode to perform the second type of synchronizing procedure, and (2) entering sleep mode.
13. The method of claim 10 , wherein the step of determining whether the serving cell is acceptable to stay camped-on comprises:
waking-up a predetermined first time before a start time of a paging cycle based on the first DRX mode;
tuning to a radio frequency of a beacon channel of the serving cell and measuring a Received Signal Strength Indicator (RSSI) of the beacon channel of the serving cell; and
comparing the RSSI to a threshold value, wherein when the RSSI is greater than the threshold value then the result of the determination is that the serving cell is acceptable to stay camped-on, and when the RSSI is less than the threshold value then the result of the determination is that the serving cell is not acceptable to stay camped-on.
14. The method of claim 10 , wherein the first type of synchronizing procedure comprises:
reading a predetermined number of bursts from a received beacon channel of the serving cell;
searching for a Training Sequence Code (TSC) in the read bursts to confirm cell identification of the serving cell;
performing Automatic Frequency Control (AFC) operations and Automatic Time Control (ATC) operations; and
scheduling for reception of the radio block.
15. The method of claim 10 , wherein based on the result of the determination that the serving cell is not acceptable to stay camped-on or the mobile station is not able to read the radio block message, waking-up a predetermined second time before a start time of a next paging cycle based on the first DRX mode to perform the second type of synchronizing procedure.
16. The method of claim 10 , wherein the second type of synchronizing procedure comprises:
performing Received Signal Strength Indicator (RSSI) measurement for different frequencies;
performing Frequency Correction Channel (FCCH) search;
performing Synchronization Channel (SCH) search; and
reading Broadcast Control Channel (BCCH) information.
17. The method of claim 10 , wherein based on the result of the determination that the serving cell is not acceptable to stay camped-on:
immediately performing the second type of synchronizing procedure;
scheduling readings of up to N radio blocks to be received per the legacy second DRX mode, wherein N>1; and
when one of the N radio blocks is successfully read, (1) performing an action based on content of the read one of the N radio blocks, (2) scheduling a next wake-up time based on the first DRX mode to determine whether the serving cell is acceptable to stay camped-on, and (3) entering sleep mode; or
when none of the N radio blocks is successfully read, (1) scheduling a next wake-up time based on the first DRX mode to perform the second type of synchronizing procedure, and (2) entering sleep mode.
18. The method of claim 10 , wherein the radio block is one of the following: a paging block, a Common Control Channel (CCCH) block, a paging message, or a paging notification.
19. A base station subsystem (BSS) configured to implement paging cycles for a mobile station in a cellular network, the BSS comprising:
at least one processor; and,
at least one memory that stores processor-executable instructions, wherein the at least one processor interfaces with the at least one memory to execute the processor-executable instructions, whereby said BSS is operable to:
receive, from a core network node in the cellular network, a message containing information the BSS needs to generate and transmit on a radio interface a radio block for the mobile station;
transmit the radio block according to a first Discontinuous Reception (DRX) mode rather than a legacy second DRX mode in one or more cells of a paging area of the mobile station, wherein the first DRX mode has a longer time period than the legacy second DRX mode;
keep track of the radio block transmitted according to the first DRX mode to the mobile station longer than the BSS keeps track of a radio block transmitted to another mobile station according to the legacy second DRX mode; and
upon determining that a paging response was not received from the mobile station after a predetermined time, retransmit the radio block to the mobile station without involving the core network node; or
upon receiving an indication from the mobile station indicating non-reception of the radio block, retransmit the radio block to the mobile station without involving the core network node.
20. The BSS of claim 19 , further operable to:
upon determining that a paging response was not received from the mobile station, after a predetermined time, repeatedly transmit the radio block up to N times in the one or more cells of the paging area, wherein the radio block is repeatedly transmitted up to N times according to a legacy second DRX mode.
21. The BSS of claim 19 , wherein the radio block is one of the following: a paging block, a Common Control Channel (CCCH) block, a paging message, or a paging notification.
22. A method in a base station subsystem (BSS) for implementing paging cycles for a mobile station in a cellular network, the method comprising:
receiving, from a core network node in the cellular network, a message containing the information the BSS needs to generate and transmit on a radio interface a radio block for the mobile station;
transmitting the radio block according to a first Discontinuous Reception (DRX) mode rather than a legacy second DRX mode in one or more cells of a paging area of the mobile station, wherein the first DRX mode has a longer time period than the legacy second DRX mode;
keeping track of the radio block transmitted according to the first DRX mode to the mobile station longer than the BSS keeps track of a radio block transmitted to another mobile station according to the legacy second DRX mode; and
upon determining that a paging response was not received from the mobile station, after a predetermined time, retransmitting the radio block to the mobile station without involving the core network node; or
upon receiving an indication from the mobile station indicating non-reception of the radio block, retransmitting the radio block to the mobile station without involving the core network node.
23. The method of claim 22 , further comprising:
upon determining that a paging response was not received from the mobile station, after a predetermined time, repeatedly transmit the radio block up to N times in the one or more cells of the paging area, wherein the radio block is repeatedly transmitted up to N times according to a legacy second DRX mode.
24. The method of claim 22 , wherein the radio block is one of the following: a paging block, a Common Control Channel (CCCH) block, a paging message, or a paging notification.