Checking fingerprint samples for a radio model

An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to perform:

• obtain at least one fingerprint sample for at least one communication node, wherein each fingerprint sample of the at least one fingerprint sample comprises results of a measurement performed by a mobile device at a particular position on a signal of a communication node of the at least one communication node including at least a signal strength related value;
• determine, for at least one fingerprint sample of the at least one fingerprint sample, whether the respective fingerprint sample fulfils an inconsistency criterion, wherein the inconsistency criterion is based on the signal strength related value of the respective fingerprint sample and a distance value indicative of an estimated distance between the mobile device and the communication node associated with the fingerprint sample;
• and
• determine a value related to a signal strength of a transmitted signal of the communication node associated with the respective fingerprint sample at the communication node based on:
• a maximum value of a set of one or more signal strength related values associated with the communication node;
• and
• an estimated value related to an altitude of the communication node,
• wherein the inconsistency criterion is further based on the value related to the signal strength of the transmitted signal of the communication node associated with the respective fingerprint sample at the communication node.

A non-transitory_computer readable storage medium in which computer program code is stored, the computer program code causing an apparatus to perform the following when executed by a processor:

• obtain at least one fingerprint sample for at least one communication node, wherein each fingerprint sample of the at least one fingerprint sample comprises results of a measurement performed by a mobile device at a particular position on a signal of a communication node of the at least one communication node including at least a signal strength related value;
• determine, for at least one fingerprint sample of the at least one fingerprint sample, whether the respective fingerprint sample fulfils an inconsistency criterion, wherein the inconsistency criterion is based on the signal strength related value of the respective fingerprint sample and a distance value indicative of an estimated distance between the mobile device and the communication node associated with the fingerprint sample;
• and
• determine a value related to a signal strength of a transmitted signal of the communication node associated with the respective fingerprint sample at the communication node based on:
• a maximum value of a set of one or more signal strength related values associated with the communication node;
• and
• an estimated value related to an altitude of the communication node,
• wherein the inconsistency criterion is further based on the value related to the signal strength of the transmitted signal of the communication node associated with the respective fingerprint sample at the communication node.