Methods and apparatus for associating carriers in a wireless communication network

1. A method in a wireless terminal device, the wireless terminal device being configurable with a plurality of carriers for communication with one or more network nodes of a wireless network, the plurality of carriers comprising a first carrier operated by a first network node of the wireless network located at a first cell site, the method comprising:

responsive to a determination that a second carrier of the plurality of carriers is operated by the first network node or a second network node of the wireless network that is located at the first cell site:

obtaining one or more measured values for one or more radio characteristics for the first carrier;

utilizing the one or more measured values to determine radio resources for transmission of a wireless radio message over the second carrier; and

transmitting the wireless radio message over the second carrier using the determined radio resources; and

wherein utilizing the one or more measured values to determine the radio resources for transmission of the wireless radio message over the second carrier based on the one or more measured values comprises:

determining a coverage level for the second carrier based on the one or more measured values; and

determining the radio resources for transmission of the wireless radio message over the second carrier, based on the coverage level.

2. The method according to claim 1 , wherein the first carrier is an anchor carrier, and the second carrier is a non-anchor carrier.

3. The method according to claim 1 , wherein obtaining the one or more measured values comprises performing measurements on the first carrier in order to obtain the one or more measured values for the one or more radio characteristics.

4. The method according to claim 1 , wherein the one or more radio characteristics comprise one or both of: signal strength and signal quality.

5. The method according to claim 1 , wherein determining the coverage level for the second carrier comprises mapping the one or more measured values to one of a plurality of discrete values for the coverage level for the second carrier.

6. The method according to claim 1 , wherein determining the coverage level comprises:

determining a path loss between the wireless terminal device and the first network node based on the one or more measured values; and

determining the coverage level for the second carrier based on the determined path loss.

7. The method according to claim 1 , wherein the determined radio resources are resources for transmission of a random access preamble on the second carrier.

8. The method according to claim 1 , wherein, with respect to determining that the second carrier is operated by the first network node or a second network node that is located at the first cell site, the wireless terminal device assumes that the second carrier is operated by the first network node or a second network node that is located at the first cell site, based on an operational mode of the wireless terminal device.

9. A method in a wireless terminal device, the wireless terminal device being configurable with a plurality of carriers for communication with one or more network nodes of a wireless network, the plurality of carriers comprising a first carrier operated by a first network node of the wireless network located at a first cell site, the method comprising:

responsive to a determination that a second carrier of the plurality of carriers is operated by the first network node or a second network node of the wireless network that is located at the first cell site:

obtaining one or more measured values for one or more radio characteristics for the first carrier;

utilizing the one or more measured values to determine radio resources for transmission of a wireless radio message over the second carrier; and

transmitting the wireless radio message over the second carrier using the determined radio resources; and

wherein the method further comprises determining whether the second carrier is operated by the first network node or a second network node that is located at the first cell site based on at least one of:

determining whether respective distances determined by the wireless terminal device for the first and second carriers are within a threshold distance difference, or determining whether respective path losses determined by the wireless terminal device for the first and second carriers are within a threshold pathloss difference.

10. A method in a wireless terminal device, the wireless terminal device being configurable with a plurality of carriers for communication with one or more network nodes of a wireless network, the plurality of carriers comprising a first carrier operated by a first network node of the wireless network located at a first cell site, the method comprising:

responsive to a determination that a second carrier of the plurality of carriers is operated by the first network node or a second network node of the wireless network that is located at the first cell site:

obtaining one or more measured values for one or more radio characteristics for the first carrier;

utilizing the one or more measured values to determine radio resources for transmission of a wireless radio message over the second carrier; and

transmitting the wireless radio message over the second carrier using the determined radio resources; and

wherein the method further comprises performing the step of utilizing the one or more measured values to determine the radio resources for transmission of the radio message over the second carrier only if one or more conditions are satisfied, and otherwise using measurements made on the second carrier to determine the radio resources for transmission of the radio message over the second carrier, and wherein the one or more conditions comprise at least one of:

the second carrier has a carrier frequency below a frequency threshold;

a frequency difference between a carrier frequency of the second carrier and a carrier frequency of the first carrier is less than a threshold amount; and

a frame timing in the second carrier is offset with respect to a frame timing in the first carrier by less than a threshold amount.

11. A wireless terminal device, the wireless terminal device being configurable with a plurality of carriers for communication with one or more network nodes of a wireless network, the plurality of carriers comprising a first carrier operated by a first network node of the wireless network located at a first cell site, the wireless terminal device comprising:

processing circuitry; and

a non-transitory machine-readable medium storing code that, when executed by the processing circuitry, causes the wireless terminal device to, responsive to a determination that a second carrier of the plurality of carriers is operated by the first network node or a second network node of the wireless network that is located at the first cell site:

obtain one or more measured values for one or more radio characteristics for the first carrier;

utilize the one or more measured values to determine radio resources for transmission of a wireless radio message over the second carrier; and;

transmit the wireless radio message over the second carrier using the determined radio resources; and

wherein the non-transitory machine-readable medium further stores code that, when executed by the processing circuitry, causes the wireless terminal to:

determine a coverage level for the second carrier based on the one or more measured values, and

determine the radio resources to transmit the wireless radio message over the second carrier based on the coverage level.

12. The wireless terminal device according to claim 11 , wherein the first carrier is an anchor carrier, and the second carrier is a non-anchor carrier.

13. The wireless terminal device according to claim 11 , wherein the wireless terminal device is configured to obtain one or more measured values by performing measurements on the first carrier in order to obtain the one or more measured values for the one or more radio characteristics.

14. The wireless terminal device according to claim 11 , wherein the determined radio resources are used for transmission of a random access preamble over the second carrier by the wireless terminal device.

15. A wireless terminal device, the wireless terminal device being configurable with a plurality of carriers for communication with one or more network nodes of a wireless network, the plurality of carriers comprising a first carrier operated by a first network node of the wireless network located at a first cell site, the wireless terminal device comprising:

processing circuitry; and

a non-transitory machine-readable medium storing code that, when executed by the processing circuitry, causes the wireless terminal device to, responsive to a determination that a second carrier of the plurality of carriers is operated by the first network node or a second network node of the wireless network that is located at the first cell site:

obtain one or more measured values for one or more radio characteristics for the first carrier;

utilize the one or more measured values to determine radio resources for transmission of a wireless radio message over the second carrier; and;

transmit the wireless radio message over the second carrier using the determined radio resources; and

wherein the non-transitory machine-readable medium further stores code that, when executed by the processing circuitry, causes the wireless terminal device to:

determine whether the second carrier is operated by the first network node or a second network node that is located at the first cell site based on at least one of:

determining whether respective distances determined by the wireless terminal device for the first and second carriers are within a threshold distance difference, or determining whether respective path losses determined by the wireless terminal device for the first and second carriers are within a threshold pathloss difference.