Measurements for indoor navigation

A mobile device comprising:

• a transceiver;
• and
• a measurement module communicatively coupled to the transceiver and configured to:
• perform a passive measurement for signals from access points;
• and
• perform a first active measurement for a first set of the access points in response to the measurement module receiving signals from the first set of the access points during the passive measurement, wherein to perform the first active measurement the measurement module is configured to:
• send at least one first communication, via the transceiver, with each first communication being sent toward a respective one of the access points of the first set of the access points;
• and
• receive at least one second communication, via the transceiver, each of which corresponds to, and is responsive to, one of the at least one first communication and is received from a corresponding one of the access points of the first set of the access points;
• wherein the measurement module is configured to perform each of the passive measurement and the first active measurement repeatedly with the first set of the access points being reestablished at each repeat performance of the passive measurement, and with the passive measurement being performed less often than the first active measurement.

A mobile device comprising:

• passive measuring means for performing a passive measurement for signals from access points;
• and
• first active measuring means for performing a first active measurement for a first set of the access points in response to the passive measuring means receiving signals from the first set of the access points during the passive measurement, wherein to perform the first active measurement the first active measuring means is configured to:
• send at least one first communication, with each first communication being sent toward a respective one of the access points of the first set of the access points;
• and
• receive at least one second communication each of which corresponds to, and is responsive to, one of the at least one first communication and is received from a corresponding one of the access points of the first set of the access points;
• wherein the passive measuring means and the first active measuring means are configured to perform each of the passive measurement and the first active measurement repeatedly with the first set of the access points being reestablished at each repeat performance of the passive measurement, and with the passive measurement being performed less often than the first active measurement.

A processor-readable storage medium comprising processor-readable instructions configured to cause a processor to:

• perform a passive measurement for signals from access points;
• and
• perform a first active measurement for a first set of the access points in response to receiving signals from the first set of the access points during the passive measurement, wherein to perform the first active measurement, the instructions are configured to cause the processor to:
• send at least one first communication, with each first communication being sent toward a respective one of the access points of the first set of the access points;
• and
• receive at least one second communication each of which corresponds to, and is responsive to, one of the at least one first communication and is received from a corresponding one of the access points of the first set of the access points;
• wherein the instructions are configured to cause the processor to perform each of the passive measurement and the first active measurement repeatedly with the first set of the access points being reestablished at each repeat performance of the passive measurement, and with the passive measurement being performed less often than the first active measurement.