Detection method for phase-modulated symbols with a correlator-bank

An apparatus for the detection of a symbol from a received signal wherein the symbol is a selected symbol out of a predetermined set of symbols, wherein each symbol of the predetermined set is a symbol comprising a sequence of chips wherein each of the chips is phase shift keying modulated according to a selected modulation code wherein each of the selected modulation codes comprises a first sub-modulation code which is a selection from a plurality of first sets of predetermined phase modulating elements and a second sub-modulation code which is a selection from one second set of predetermined phase modulating elements wherein at least one of said predetermined phase modulating elements of said second set is a complex value, the apparatus comprising:

• a first correlator bank for correlating the received signal with each of the possible first sub-modulation codes for obtaining first correlation results;
• a first selector for selecting a first correlation result from the first correlation results;
• a second correlator bank for phase-modulating the first correlation result with one of said possible second sub-modulation codes for each possible second sub-modulation code for obtaining second correlation results;
• a second selector for selecting a maximum second correlation result from the second correlation results;
• a control-unit that controls the first selector on the basis of the first correlation results;
• and
• a third selector for selecting the symbol of the received signal on the basis of the selected first correlation result and the selected maximum second correlation result.