Method and system for simultaneous receiver calibration and object localisation for multilateration

A processing unit apparatus for use in a system for multilateration of at least one of a plurality of P objects, each of the plurality of P objects having a transmitter device, and each of the transmitter devices being configured to transmit a respective signal, each of a plurality of N sensors adapted to receive the transmitted signals from each of the objects and to measure respective receive times of each of the signals, the processing unit apparatus adapted to be operatively coupled to the plurality of sensors and to perform steps comprising:

• A. combining the receive times for the signals into a chronologically ordered series of message sets, wherein each of the message sets comprises the receive times of one of the transmitted signals as determined by each sensor;
• B. collecting all valid message sets that occur within a predetermined time interval ΔTk, wherein the index kε{1, . . . , NΔT} denotes a time step, and wherein each valid message set contains receive times from at least N sensors;
• C. estimating a time offset vector ok comprising time offsets oki of the receive times of the N sensors at time step k and iε{1, . . . , N} by processing at least one of the message sets;
• and
• D. outputting a position of said at least one of the plurality of objects.