Abstract: An FIR filter of a DS-CDMA UWB modem transmitter and a control method thereof are disclosed. The FIR filter includes an LUT control device for outputting a resultant value of “0” to all adders if data values corresponding to upper three chips H2, M2 and L2 and lower three chips H, M and L are “000000”, and discriminating which group between a first group and a second group the upper/lower data values belong to if the upper/lower data values are not “000000”. The LUT control device provides upper or lower LUT values to the adders using the upper or lower LUT values as they are, or converts the upper or lower LUT values into 2's complements and provides the converted values to the adders according to the discriminated first or second group. The FIR filter has the effect of reducing the amount of memory by about 50% to 80% in comparison to the conventional FIR filter.

Abstract: There is provided a code acquisition device and method using a two-step search process in a DS-CDMA UWB modem. The device includes: an I/Q channel symbol generating unit for, generating a plurality (i) of nth I/Q channel symbols in a first search process and generating a plurality of nth I/Q channel symbols in a second search process; a spread code selecting unit for receiving the plurality of nth I/Q channel symbols in the first search process; an NNC2NS tap I/Q channel symbol matched filter unit for, in the second search process, receiving the plurality (i) of nth I/Q channel symbols; a switching unit for changing to a closed state of the second search process; and a super frame and symbol boundary time deciding unit for deciding a super frame time and a symbol boundary time.

Abstract: Provided are an initial synchronization acquiring device and method in a parallel processed DS-CDMA UWB system and a DS-CDMA UWB system's receiver using the same. The initial synchronization acquiring device is constructed to include a correlator for correlating input signals and outputting correlation result values and an initial synchronizer for tuning initial symbol synchronization and frame synchronization by using the correlation result values received from the correlator and then storing combining mark values and a synchronization position value in a register, thereby making it possible to greatly decrease a system's complexity, compared to the existing method of separately designing respective modules for acquiring packet synchronization and symbol synchronization in the existing CDMA system.