Patent ID: 7047247

Claim:
A method of encoding reference objects with reference to a traffic route network in a transmitter, transmitting the reference objects in encoded form from the transmitter to a receiver via a transmission system and decoding the reference objects in encoded form in the receiver, wherein said transmitter includes an encoder and a database associated with the encoder, said receiver includes a decoder and a database associated with the decoder and the database in the transmitter differs from the database in the receiver, said method comprising the steps of: a) encoding a reference object from the database of the transmitter together with relationship information by means of the encoder to generate encoded information, said relationship information comprising location references for the reference object and defining at least one relationship of the reference object to at least one relational object present in the database of the receiver; b) transmitting the encoded information from the transmitter to the receiver via the transmission system; c) decoding the relationship information including the location references for the reference object in the decoder to ascertain the at least one relationship of the reference object to the at least one relational object already present in the database of the receiver; d) searching at least a predetermined portion of the database of the receiver to determine if the reference object is already present in the database of the receiver; and e) storing the reference object in the database of the receiver according to the at least one relationship of the reference object to the at least one relational object determined in the decoding of step c) if the searching of step d) establishes that the reference object is not already present in the database of the receiver.