Configuring discovery signals

1. A method in a first network node, comprising:

receiving, from one or more wireless devices, an indication that the first network node should adapt one or more discovery reference signal parameters;

determining a time synchronization level for at least a pair of network nodes, the time synchronization level comprising information about a difference in start time of radio frames in a downlink or radio subframes in a downlink between the at least a pair of network nodes, wherein the determining comprises one or more of:

determining the time synchronization level for the at least a pair of network nodes based at least in part on pre-defined information;

receiving information about the time synchronization level for the at least a pair of network nodes; and

determining the time synchronization level for the at least a pair of network nodes based at least in part on one or more of historical data or a previously assumed synchronization level;

adapting the one or more discovery reference signal parameters based at least in part on the determined time synchronization level for the at least a pair of network nodes and further based at least in part on whether the determined time synchronization level is larger than a threshold time, responsive to receiving the indication, wherein the one or more discovery reference signal parameters comprise one or more of:

a discovery reference signal periodicity;

a discovery reference signal bandwidth; and

a duration of a discovery reference signal burst; and

transmitting a discovery reference signal using the adapted one or more discovery reference signal parameters.

2. The method of claim 1 , further comprising communicating information about the adapted one or more discovery reference signal parameters to another node.

3. The method of claim 1 , wherein adapting the one or more discovery reference signal parameters is further based at least in part on the indication received from the one or more wireless devices indicating that the first network node should adapt the one or more discovery reference signal parameters.

4. The method of claim 1 , wherein the at least a pair of network nodes comprises one of:

the first network node and a neighboring network node;

the first network node and one or more neighboring network nodes within a threshold range of the first network node; and

a second network node and a third network node.

5. A method in a wireless device, comprising:

determining a time synchronization level between one or more cells, wherein the time synchronization level comprises information about a difference in start time of radio frames in a downlink or radio subframes in a downlink between the one or more cells, wherein determining the time synchronization level between the one or more cells comprises determining the time synchronization level between the one or more cells based on received timings of the one or more cells acquired by the wireless device during a cell identification procedure;

determining whether to communicate an indication to a first network node indicating that the first network node should adapt one or more discovery reference signal parameters based at least in part on the determined time synchronization level between the one or more cells and further based at least in part on whether the determined time synchronization level is larger than a threshold time, wherein the one or more discovery reference signal parameters comprise one or more of:

a discovery reference signal periodicity;

a discovery reference signal bandwidth; and

a duration of a discovery reference signal burst; and

communicating the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters.

6. The method of claim 5 , wherein determining whether to communicate the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters is based at least in part on one or more of:

the determined time synchronization level between the one or more cells; and

one or more radio measurements performed by the wireless device on the one or more cells with discovery reference signal transmission on a carrier.

7. The method of claim 5 , wherein communicating the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters comprises one or more of:

sending a request that the one or more discovery reference signal parameters be adapted; and

indicating that the one or more discovery reference signal parameters should be adapted to one of a denser level or a coarser level with respect to one or more reference values.

8. The method of claim 5 , further comprising receiving information about the adapted one or more discovery reference signal parameters from the first network node.

9. The method of claim 8 , further comprising using the received information about the adapted one or more discovery reference signal parameters to perform one or more radio operations, the one or more radio operations comprising one or more of:

adapting one or more parameters used for radio measurements on discovery reference signals; and

determining a synchronization level used in a network.

10. A first network node, comprising:

one or more processors configured to:

receive, from one or more wireless devices, an indication that the first network node should adapt one or more discovery reference signal parameters;

determine a time synchronization level for at least a pair of network nodes, the time synchronization level comprising information about a difference in start time of radio frames in a downlink or radio subframes in a downlink between the at least a pair of network nodes, wherein, in order to determine the time synchronization level for the at least a pair of network nodes, the one or more processors are further configured to perform one or more of:

determine the time synchronization level for the at least a pair of network nodes based at least in part on pre-defined information;

receive information about the time synchronization level for the at least a pair of network nodes; and

determine the time synchronization level for the at least a pair of network nodes based at least in part on one or more of historical data or a previously assumed synchronization level;

adapt the one or more discovery reference signal parameters based at least in part on the determined time synchronization level for the at least a pair of network nodes and further based at least in part on whether the determined time synchronization level is larger than a threshold time, responsive to receiving the indication, wherein the one or more discovery reference signal parameters comprise one or more of:

a discovery reference signal periodicity;

a discovery reference signal bandwidth; and

a duration of a discovery reference signal burst; and

transmit a discovery reference signal using the adapted one or more discovery reference signal parameters.

11. The first network node of claim 10 , wherein the one or more processors are further configured to communicate information about the adapted one or more discovery reference signal parameters to another node.

12. The first network node of claim 10 , wherein the one or more processors are configured to adapt the one or more discovery reference signal parameters based at least in part on the determined time synchronization level for the at least a pair of network nodes and further based at least in part on the indication received from the one or more wireless devices indicating that the first network node should adapt the one or more discovery reference signal parameters.

13. The first network node of claim 10 , wherein the at least a pair of network nodes comprises one of:

the first network node and a neighboring network node;

the first network node and one or more neighboring network nodes within a threshold range of the first network node; and

a second network node and a third network node.

14. A wireless device, comprising:

one or more processors configured to:

determine a time synchronization level between one or more cells, wherein the time synchronization level comprises information about a difference in start time of radio frames in a downlink or radio subframes in a downlink between the one or more cells, wherein determining the time synchronization level between the one or more cells comprises determining the time synchronization level between the one or more cells based on received timings of the one or more cells acquired by the wireless device during a cell identification procedure;

determine whether to communicate an indication to a first network node indicating that the first network node should adapt one or more discovery reference signal parameters based at least in part on the determined time synchronization level between the one or more cells and further based at least in part on whether the determined time synchronization level is larger than a threshold time, wherein the one or more discovery reference signal parameters comprise one or more of:

a discovery reference signal periodicity;

a discovery reference signal bandwidth; and

a duration of a discovery reference signal burst; and

communicate the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters.

15. The wireless device of claim 14 , wherein the one or more processors configured to determine whether to communicate the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters comprise one or more processors configured to determine whether to communicate the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters is based at least in part on one or more radio measurements performed by the wireless device on the one or more cells with discovery reference signal transmission on a carrier.

16. The wireless device of claim 14 , wherein the one or more processors configured to communicate the indication to the first network node indicating that the first network node should adapt the one or more discovery reference signal parameters comprise one or more processors configured to perform one or more of:

send a request that the one or more discovery reference signal parameters be adapted; and

indicate that the one or more discovery reference signal parameters should be adapted to one of a denser level or a coarser level with respect to one or more reference values.

17. The wireless device of claim 14 , wherein the one or more processors are further configured to receive information about the adapted one or more discovery reference signal parameters from the first network node.

18. The wireless device of claim 17 , wherein the one or more processors are further configured to use the received information about the adapted one or more discovery reference signal parameters to perform one or more radio operations, the one or more radio operations comprising one or more of:

adapting one or more parameters used for radio measurements on discovery reference signals; and

determining a synchronization level used in a network.