HANDOVER PROCESSING IN MULTIPLE ACCESS POINT DEPLOYMENT SYSTEM
This disclosure relates to method, device and system for performing handover processing. A roaming list is configured at a receiver which includes multiple entries. Each entry of the roaming list includes receive parameters. A measurement operation is performed on an entry of the roaming list. A transmitter is set based on the measurement operation. Finally, an uplink signal is transmitted to an access point at a time based on a slot start time and a random timing offset. The uplink signal is transmitted while a second signal is transmitted from another node.
1 . A method of handover processing comprising:
configuring at a receiver a roaming list comprising a plurality of entries, wherein each entry comprises one or more receive parameters of the receiver;
performing a measurement operation at the receiver on a current entry of the roaming list;
selecting an entry of the roaming list based on the measurement operation;
setting a transmitter based on the selected entry of the roaming list; and
transmitting an uplink signal to an access point at a time based on a slot start time and a random timing offset, and wherein the uplink signal is transmitted while at least a portion of a second signal is transmitted from a second node such that both the uplink signal and the second signal are received.
2 . The method of claim 1 , wherein an entry of the roaming list comprises a center frequency and a gold code.
3 . The method of claim 1 , wherein the roaming list is received by the receiver during a prior transmission.
4 . The method of claim 3 , wherein the roaming list is received by the receiver at a particular prearranged time.
5 . The method of claim 3 , wherein the roaming list is received by the receiver at a particular prearranged frequency and at a particular prearranged gold code.
6 . The method of claim 1 , wherein the measurement operation comprises setting the receiver based on the current entry, measuring an RSSI metric at the receiver, and recording the RSSI metric; and wherein the entry of the roaming list is selected based on a greatest RSSI metric.
7 . The method of claim 6 , wherein the RSSI metric is based in part on a downlink RSSI measurement minus an access point interference signal.
8 . The method of claim 1 , wherein the measurement operation comprises recording a frequency estimate and a timing estimate into the roaming list based on a successful demodulation of a broadcast channel and wherein the receiver is set based on a recorded frequency estimate and a recorded timing estimate.
9 . The method of claim 1 , wherein the roaming list is ordered into a priority list based on previous iterations of the measurement operation.
10 . The method of claim 9 , further comprising:
moving the selected entry to a last entry of the priority list;
repeating the measurement operation for each entry in the priority list;
selecting a second entry of the priority list based in part on a second measurement operation; and
setting the transmitter based on the selected second entry of the roaming list.
11 . The method of claim 1 , wherein repeating the measurement operation for each entry of the roaming list is interrupted when the measurement operation produces a result greater than a threshold value.
12 . A node comprising:
a processor;
a receiver operatively coupled to the processor and configured to
configure a roaming list comprising a plurality of entries, wherein each entry comprises one or more receive parameters of the receiver;
perform a measurement operation on a current entry of the roaming list;
select an entry of the roaming list based in part on the measurement operation;
set a transmitter based on the selected entry of the roaming list; and
transmit an uplink signal to an access point at a time based on a slot start time and a random timing offset, and wherein the uplink signal is transmitted while at least a portion of a second signal is transmitted from a second node such that both the uplink signal and the second signal are received.
13 . The node of claim 12 , wherein the roaming list is received by the receiver during a prior transmission.
14 . The node of claim 12 , wherein the roaming list is received by the receiver at a particular prearranged frequency and at a particular prearranged gold code.
15 . The node of claim 12 , wherein the measurement operation comprises setting the receiver based on the current entry, measuring an RSSI metric at the receiver, and recording the RSSI metric; and wherein the entry of the roaming list is selected based on a greatest RSSI metric.
16 . The node of claim 12 , wherein the receiver is further configured to:
order the roaming list into a priority list based on previous iterations of the measurement operation;
move the selected entry to a last entry of the priority list;
repeat the measurement operation for each entry in the priority list;
select a second entry of the priority list based in part on a second measurement operation; and
set the transmitter based on the selected second entry of the roaming list.
17 . A system comprising:
a first access point comprising
a first downlink transmitter configured to transmit with a first transmit parameter;
a second access point comprising
a second downlink transmitter configured to transmit with a second transmit parameter; and
a node comprising
a processor,
a receiver operatively coupled to the processor and configured to
configure a roaming list comprising a plurality of entries, wherein a first entry comprises the first transmit parameter and a second entry comprises the second transmit parameter,
perform a measurement operation on a current entry of the roaming list,
select an entry of the roaming list based in part on a greatest RSSI metric,
set a transmitter based on the selected entry of the roaming list, and
transmit an uplink signal to an access point at a time based on a slot start time and a random timing offset, and wherein the uplink signal is transmitted while at least a portion of a second signal is transmitted from a second node such that both the uplink signal and the second signal are received.
18 . The system of claim 17 , wherein the roaming list is received by the receiver during a prior transmission.
19 . The system of claim 17 , wherein the roaming list is received by the receiver at a particular prearranged frequency and at a particular prearranged gold code.
20 . The system of claim 17 , wherein the receiver is further configured to:
order the roaming list into a priority list based on previous iterations of the measurement operation;
move the selected entry to a last entry of the priority list;
repeat the measurement operation for each entry in the priority list;
select a second entry of the priority list based in part on a second measurement operation; and
set the receiver based on the selected second entry of the roaming list.