COMPRESSING AND DECOMPRESSING DATA ABOUT RADIO SIGNALS
摘要
An apparatus obtains a set of radio data comprising signal strength related values for radio signals transmitted by a transmitter with an association of each signal strength related value with a representation of a geographical location (201). The apparatus applies a frequency transform to the obtained set of radio data to obtain transform coefficients, each transform coefficient comprising a transform index and an associated transform value (202). The apparatus selects a subset of transform indices having more significant transform values than the remaining transform indices (203) and compresses the transform indices by encoding each transform index exploiting a probability of occurrence of an index value of a respective transform index (204). The same or another apparatus decodes the compressed transform indices again for use in position operations.
申请公布号
WO2016180480(A1)
申请公布日期
2016.11.17
申请号
WO2015EP60446
申请日期
2015.05.12
申请人
HERE GLOBAL B.V.
发明人
WIROLA, Lauri;IVANOV, Pavel;KHAN, Muhammad Irshan;SYRJÄRINNE, Jari;TALVITIE, Jukka;LOHAN, Elena-Simona