Apparatus and method for scheduling correlation operations of a ds-cdma shared correlator

Abstract

An apparatus and method of a shared correlator system for a code division, multiple access (CDMA) receiver employs scheduling of correlation operations with identification tags (ID-tags). The scheduling allows for shared vector generation and correlation operations between processing units by pipeline processing. The shared correlator schedules correlation operations requested by processing units, generates matched-filter PN vectors associated with the identification tags for the correlation operations, and provides correlation results for the correlation operations. Scheduling may be implemented with a control processor, scheduler and memory. The control processor determines the matched-filter PN vector information for a requested operation using the current state of a reference PN code sequence, and this information is stored as the ID-tag. The control processor stores the ID-tag at an address in memory associated with a slot of a periodic symbol schedule. A counter of the scheduler steps through each memory address to provide an ID-tag for each slot. The ID-tag allows the matched-filter PN vector information for a requested correlation operation to be provided to the vector generator and vector correlator to generate the matched-filter PN vector for the slot.