Methods for cell selection and PLMN selection based on RACH precompensation
Systems and methods related to cell selection based on random access channel pre-compensation features supported by a wireless device are disclosed. In one embodiment, a method performed by a wireless device comprises obtaining information that indicates one or more random access channel pre-compensation features required for wireless devices to select a cell. The method further comprises making a decision as to whether the wireless device is permitted to select the cell based on the information and one or more random access channel pre-compensation features supported by the wireless device and performing one or more actions in accordance with the decision.
1 . A method performed by a wireless device, the method comprising:
obtaining information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell, wherein the information indirectly identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell by identifying one or more random access channel pre-compensation features for which the wireless device is not permitted to select the cell;
making a decision as to whether the wireless device is permitted to select the cell based on the information and one or more random access channel pre-compensation features supported by the wireless device; and
performing an action in accordance with the decision, wherein the action is selected from one of the following actions:
selecting or reselecting to the cell for which the decision was made, if the decision is that the wireless device is permitted to select to the cell; or
refraining from selecting or reselecting to the cell for which the decision was made, if the decision is that the wireless device is not permitted to select to the cell.
2 . The method of claim 1 wherein the one or more random access channel pre-compensation features comprise:
a feature by which the wireless device performs time compensation, but not frequency compensation, before starting initial access;
a feature by which the wireless device performs frequency compensation, but not time compensation, before starting initial access; or
a feature by which the wireless device performs both time compensation and frequency compensation before starting initial access.
3 . The method of claim 1 wherein the information comprises information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell on a carrier frequency.
4 . The method of claim 3 wherein making the decision as to whether the wireless device is permitted to select the cell comprises making the decision as to whether the wireless device is permitted to select the cell on the carrier frequency based on the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell on the carrier frequency.
5 . The method of claim 1 wherein the cell is a neighbor cell of either a serving cell of the wireless device or a cell on which the wireless device is camping.
6 . The method of claim 1 wherein the information comprises, for a Public Land Mobile Network, PLMN, to which the cell belongs, information that identifies one or more random access channel pre-compensation features required for the wireless device to select the cell in the PLMN.
7 . The method of claim 6 wherein making the decision as to whether the wireless device is permitted to select the cell comprises making the decision as to whether the wireless device is permitted to select the cell in a particular PLMN based on the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell in the particular PLMN.
8 . The method of claim 1 wherein the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell comprises information that specifically identifies the one or more random access channel pre-compensation features.
9 . The method of claim 1 wherein the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell comprises information that identifies one or more wireless device classes, wherein each wireless device class of the one or more wireless device classes supports a different random access channel pre-compensation feature or a different set of random access channel pre-compensation features.
10 . The method of claim 1 wherein the information directly identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell.
11 . The method of claim 1 wherein obtaining the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell comprises obtaining the information for the cell via a random access channel configuration broadcasted in system information for the particular cell.
12 . The method of claim 1 wherein obtaining the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell comprises obtaining the information via broadcasted system information.
13 . The method of claim 1 wherein the one or more random access channel pre-compensation features comprise a feature that the wireless device has a Global Navigation Satellite System, GNSS, capability.
14 . The method of claim 1 wherein the one or more random access channel pre-compensation features comprise a feature that the wireless device does not have a Global Navigation Satellite System, GNSS, capability.
15 . The method of claim 1 wherein the information is cell barring information.
16 . A wireless device comprising:
one or more transmitters;
one or more receivers; and
processing circuitry associated with the one or more transmitters and the one or more receivers, the processing circuitry configured to cause the wireless device to:
obtain information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell, wherein the information indirectly identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell by identifying one or more random access channel pre-compensation features for which the wireless device is not permitted to select the cell;
make a decision as to whether the wireless device is permitted to select the cell based on the information and one or more random access channel pre-compensation features supported by the wireless device; and
perform an action in accordance with the decision, wherein the action is selected from of the following actions:
selecting or reselecting to the cell for which the decision was made, if the decision is that the wireless device is permitted to select to the cell; or
refraining from selecting or reselecting to the cell for which the decision was made, if the decision is that the wireless device is not permitted to select to the cell.
17 . A method performed by a base station, the method comprising:
providing, to a wireless device, information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell, wherein the information indirectly identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell by identifying one or more random access channel pre-compensation features for which the wireless device is not permitted to select the cell.
18 . The method of claim 17 wherein the one or more random access channel pre-compensation features comprise:
a feature by which the wireless device performs time compensation, but not frequency compensation, before starting initial access;
a feature by which the wireless device performs frequency compensation, but not time compensation, before starting initial access; or
a feature by which the wireless device performs both time compensation and frequency compensation before starting initial access.
19 . The method of claim 17 wherein the cell is a neighbor cell of either a serving cell of the wireless device or a cell on which the wireless device is camping.
20 . The method of claim 17 wherein the cell is a cell for intra-frequency cell search or a cell for inter-frequency cell search.
21 . The method of claim 17 wherein the information comprises information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell on a carrier frequency.
22 . The method of claim 17 wherein the information comprises information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell in a Public Land Mobile Network, PLMN.
23 . The method of claim 17 wherein the information that identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell comprises information that specifically identifies the one or more random access channel pre-compensation features.
24 . A base station comprising processing circuitry configured to cause the base station to:
provide, to a wireless device, information that identifies one or more random access channel pre-compensation features required for the wireless device to select a cell, wherein the information indirectly identifies the one or more random access channel pre-compensation features required for the wireless device to select the cell by identifying one or more random access channel pre-compensation features for which the wireless device is not permitted to select the cell.