Abstract: An apparatus and method for estimating an initial frequency offset in a mobile communication system in which a user equipment (UE) performs initial cell search in order to identify a Node B with which the UE can exchange data is provided. The apparatus comprises a memory for storing a plurality of pulse duration modulation (PDM) hypotheses and storing the PDM hypotheses therein; a step#1 cell searcher for performing a step#1 cell search on each of the PDM hypotheses through a primary synchronization channel and outputting the cell search result to the memory; and an initial frequency offset estimator for determining an initial frequency offset estimation value from the cell search results for the PDM hypotheses.

Abstract: A cell search apparatus and method in a mobile communication system. After a UE acquires slot boundary timing and frame boundary timing to a Node B, it acquires its scrambling code number and scrambling code timing. After the initial cell search, the UE performs multi-path search by searching a first area with respect to the scrambling code timing. During reacquisition in a sleep state, the UE searches a second area wider than the first area with respect to a scrambling code timing acquired before the sleep state. The UE performs neighbor cell search by selectively using the initial cell search and the multi-path search according to whether the Node B provides information or what information it provides.

Abstract: A cell search method in an asynchronous mobile communication system. For cell search, a UE searches signals received from Node Bs in a slot synchronization step, calculates the timing offset of each of the Node Bs by comparing signals having slot peaks higher than a first threshold with each other among the searched signals in a frame synchronization and code group identification step, and detects the timing offsets of neighbor Node Bs by comparing the timing offsets of signals higher than a second threshold with each other in a code identification step. In addition, Node Bs that transmit signals higher than the second threshold in the code identification step are included in a candidate set and are subject to a cell search periodically.

Abstract: A method of increasing the waiting time of a mobile terminal by reducing power consumption for a cell search in a discontinuous reception mode. In an embodiment of the invention, the strengths of signals from neighbor cells are measured and compared with a first threshold. Then a cell search is performed on only neighbor cells having signal strengths higher than the first threshold. In a second embodiment of the invention, a cell search is not performed if the signal strength of an active set is higher than a second threshold in a discontinuous reception mode. In a third embodiment of the invention, an offline cell search is performed in a discontinuous reception mode in the last step of three conventional cell search steps.

Abstract: A cell search apparatus and method in a W-CDMA mobile communication system. The cell search apparatus and method performs a first cell search step, a second cell search step, and a third cell search step using a slot count value and a lower count value, counted by an index counter after being initialized upon power up of a UE (User Equipment), thereby determining a scrambling code for a Node B. Further, the cell search apparatus and method manages neighboring Node Bs by performing a multipath search.

Abstract: An apparatus and method for estimating an initial frequency offset in a mobile communication system in which a user equipment (UE) performs initial cell search in order to identify a Node B with which the UE can exchange data is provided. The apparatus comprises a memory for storing a plurality of pulse duration modulation (PDM) hypotheses and storing the PDM hypotheses therein; a step#1 cell searcher for performing a step#1 cell search on each of the PDM hypotheses through a primary synchronization channel and outputting the cell search result to the memory; and an initial frequency offset estimator for determining an initial frequency offset estimation value from the cell search results for the PDM hypotheses.

Abstract: A cell search apparatus and method in a W-CDMA mobile communication system. The cell search apparatus and method performs a first cell search step, a second cell search step, and a third cell search step using a slot count value and a lower count value, counted by an index counter after being initialized upon power up of a UE (User Equipment), thereby determining a scrambling code for a Node B. Further, the cell search apparatus and method manages neighboring Node Bs by performing a multipath search.

Abstract: A method of increasing the waiting time of a mobile terminal by reducing power consumption for a cell search in a discontinuous reception mode. In an embodiment of the invention, the strengths of signals from neighbor cells are measured and compared with a first threshold. Then a cell search is performed on only neighbor cells having signal strengths higher than the first threshold. In a second embodiment of the invention, a cell search is not performed if the signal strength of an active set is higher than a second threshold in a discontinuous reception mode. In a third embodiment of the invention, an offline cell search is performed in a discontinuous reception mode in the last step of three conventional cell search steps.

Abstract: An apparatus and method for generating cell-specific scrambling codes in an asynchronous CDMA mobile communication system. A predetermined number of base scrambling codes are stored as initial conditions. An intended scrambling code is generated by cyclically shifting or masking a corresponding base scrambling code. This provides for generating cell-specific scrambling codes at any point in time to achieve high-speed cell search.

Abstract: A cell search apparatus and method in a mobile communication system. After a UE acquires slot boundary timing and frame boundary timing to a Node B, it acquires its PN code number and PN code timing. After the initial cell search, the UE performs multi-path search by searching a first area with respect to the PN code timing. During reacquisition in a sleep state, the UE searches a second area wider than the first area with respect to a PN code timing acquired before the sleep state. The UE performs neighbor cell search by selectively using the initial cell search and the multi-path search according to whether the Node B provides information or what information it provides.

Abstract: A cell search method in an asynchronous mobile communication system. For cell search, a UE searches signals received from Node Bs in a slot synchronization step, calculates the timing offset of each of the Node Bs by comparing signals having slot peaks higher than a first threshold with each other among the searched signals in a frame synchronization and code group identification step, and detects the timing offsets of neighbor Node Bs by comparing the timing offsets of signals higher than a second threshold with each other in a code identification step. In addition, Node Bs that transmit signals higher than the second threshold in the code identification step are included in a candidate set and are subject to a cell search periodically.