Hearing devices and accessory devices having pairing capability and method of pairing hearing devices with accessory devices

An accessory device comprising:

• an antenna configured to perform electromagnetic-field emission and/or electromagnetic-field reception;
• a processing unit coupled to the antenna;
• and
• a memory storing a first accessory device parameter;
• wherein the processing unit is configured to:
• obtain the first accessory device parameter,
• obtain a first hearing device parameter received via the antenna of the accessory device,
• determine a first criterion value, and
• perform a comparison between a signal metric and the first criterion value, the signal metric indicating or being associated with a radiated power transmitted from a hearing device and received at the accessory device;
• and
• wherein the processing unit is configured to perform a pairing action when a result of the comparison satisfies a criterion, and wherein a satisfaction of the criterion indicates that the hearing device is in a pairing range;
• and
• wherein the processing unit is configured to determine the first criterion based on the first hearing device parameter and the first accessory device parameter.