Method and system for signaling in a heterogeneous network
View Patent ↗A method at a network element operating in a wireless network, wherein the network element is configured to transmit a default cell search signal at a default position in one or more subframes, the method comprising transmitting, by the network element, an auxiliary cell search signal in addition to the default cell search signal.
1. A method at a network element operating in a wireless network, the method comprising:
transmitting, by the network element, a default cell search signal, the default cell search signal comprising a default Synchronization Signal including a default Primary Synchronization Signal (‘PSS’) transmitted at symbol n1 of a first time slot and a default Secondary Synchronization Signal (‘SSS’) transmitted at a symbol n2 of the time slot, wherein (n2−n1) is equal to k;
transmitting, by the network element, an auxiliary cell search signal, the auxiliary cell search signal comprising an auxiliary Synchronization Signal including an auxiliary PSS transmitted at symbol n3 in a second time slot and an auxiliary SSS transmitted at symbol n4 in the second time slot, wherein (n3−n4) is equal to k;
receiving, at the network element, communication signals from a user equipment in response to the default cell search signal and the auxiliary cell search signal wherein the network element further signals to a user equipment to enable or disable detection of the auxiliary cell search signal.
2. The method of claim 1 , wherein n3 is predefined and wherein n3 is different from n1.
3. The method of claim 1 , wherein the auxiliary PSS occupies a different number of subcarriers compared to the default PSS.
4. The method of claim 1 , wherein the network element further exchanges information with a neighboring network element about the auxiliary cell search signal.
5. The method of claim 1 , wherein the auxiliary PSS comprises at least partially the same sequence as the default PSS.
6. The method of claim 1 , wherein the auxiliary PSS comprises a Zadoff-Chu sequence generated from a different root index than the default PSS.
7. The method of claim 1 , wherein the auxiliary SSS utilizes a different sequence from the default SSS.
8. A method at a user equipment (‘UE’) operating in a wireless network, the method comprising:
detecting, by the UE, a default cell search signal, the default cell search signal comprising a default Primary Synchronization Signal (‘PSS’) at symbol n1 of a first time slot and a default Secondary Synchronization Signal (‘SSS’) at symbol n2 of the first time slot, wherein (n2−n1) is equal to k;
detecting, by the UE, an auxiliary cell search signal, the auxiliary cell search signal comprising an auxiliary Synchronization Signal, the auxiliary Synchronization Signal including an auxiliary PSS at symbol n3 of a second time slot and an auxiliary SSS at subframe n4 of the second time slot, wherein (n3−n4) is equal to k; and
utilizing, by the UE, information within the auxiliary cell search signal to detect a cell for the wireless network.
9. The method of claim 8 , wherein the auxiliary cell search signal is located at a predetermined location within a radio frame.
10. The method of claim 8 , further comprising detecting a cell for the wireless network using both the detected auxiliary cell search signal and the default cell search signal for decoding.
11. The method of claim 8 , wherein the detecting is performed only upon receipt of explicit signaling.
12. The method of claim 8 , wherein the explicit signaling is radio resource control signaling.
13. The method of claim 8 , wherein the auxiliary PSS occupies a different number of subcarriers compared to the default PSS.
14. The method of claim 8 , wherein the auxiliary PSS comprises at least partially the same sequence as the default PSS.
15. The method of claim 8 , wherein the auxiliary PSS comprises a Zadoff-Chu sequence generated from a different root index than the default PSS.
16. The method of claim 8 , wherein the auxiliary SSS utilizes a different sequence from the default SSS.
17. A network element operating in a wireless network, comprising:
a processor; and
a communications subsystem,
wherein the processor and communications subsystem cooperate to:
transmit a default cell search signal, the default cell search signal comprising a default Synchronization Signal including a default Primary Synchronization Signal (‘PSS’) transmitted at symbol n1 of a first time slot and a default Secondary Synchronization Signal (‘SSS’) transmitted at a symbol n2 of the first time slot, wherein (n2−n1) is equal to k;
transmit an auxiliary cell search signal, the auxiliary cell search signal comprising an auxiliary Synchronization Signal including an auxiliary PSS transmitted at symbol n3 of a second time slot and an auxiliary SSS transmitted at symbol n4 of the second time slot, wherein (n3−n4) is equal to k
receive, at the network element, communication signals from a user equipment in response to the default cell search signal and the auxiliary cell search signal wherein the network element further signals to a user equipment to enable or disable detection of the auxiliary cell search signal.
18. The network element of claim 17 , wherein transmitting the auxiliary PSS comprises transmitting the auxiliary PSS in a same sub-frame as a default cell search signal.
19. The network element of claim 17 , wherein n3 is predetermined, and wherein n3 is different from n1.
20. The network element of claim 17 , wherein the auxiliary PSS occupies a different number of subcarriers compared to the default PSS.
21. The network element of claim 17 , wherein the auxiliary PSS comprises at least partially the same sequence as the default PSS.
22. The network element of claim 17 , wherein the auxiliary PSS comprises a Zadoff-Chu sequence generated from a different root index than the default PSS.
23. The network element of claim 17 , wherein the auxiliary SSS utilizes a different sequence from the default SSS.