Abstract—Code synchronization is a critical step for fast and reliable code search in directsequence spread-spectrum (DS-SS) system. In this paper, we propose a novel differentially coherent (DC) detection scheme for rapid code acquisition over a fast Rayleigh fading mobile radio channel with frequency offset, and compare the performance with the conventional I-Q noncoherent detection scheme. N...

1 Pseudo-Random Sequences ....................................2 1.1 Randomness Properties ........................................... 2 1.2 Generating Pseudo-Random Sequences ..................2 2 Scrambling Codes for WCDMA .............................2 2.1 Generating Long Complex Scrambling Codes ....... 3 2.2 Scrambling an I-Q/Code Multiplexed Sign ......... al 6 3 Software Implementation on...

1 Pseudo-Random Sequences ....................................2 1.1 Randomness Properties ........................................... 2 1.2 Generating Pseudo-Random Sequences ..................2 2 Scrambling Codes for WCDMA .............................2 2.1 Generating Long Complex Scrambling Codes ....... 3 2.2 Scrambling an I-Q/Code Multiplexed Sign ......... al 6 3 Software Implementation on...

A microcellular local area network (LAN) for indoor communications is proposed using code division multiple access (CDMA) and DPSK for data modulation. The pseudonoise (PN) codes in the transmitters of the base station are mutually synchronized. For this purpose, sets of Gold code sequences having low cross correlation have been found by an exhaustive computer search. Together with wideband mea...

A Generalized Frequency Hopping (GFH) OFDMA system is developed in this paper as a structured long code DS-CDMA system in order to bridge frequency hopped multi-carrier transmissions with long code DS-CDMA. Through judicious code design, multiuser interference is eliminated deterministically in the presence of unknown frequency-selective multipath channels. Thanks to frequency hopping, no singl...

In this paper, signed-rank based nonparametric detectors are used for pseudonoise (PN) code acquisition in frequency-selective Rician fading channels. We first derive the locally optimum rank detector and then propose the locally suboptimum rank (LSR) and th order modified signed-rank (MSR ) detectors using approximate score functions. We compare the hybrid parallel double-dwell scheme using th...

In this paper, signed-rank based nonparametric detectors are used for pseudonoise (PN) code acquisition in direct sequence spread spectrum (DS/SS) systems. We first derive the locally optimum rank (LOR) detector, and then propose a locally suboptimum rank (LSR) detector and a modified signed-rank (MSR) detector using approximate score functions. We compare the single-dwell scheme without the ve...

AbsfractThis paper computes the probabilities of detection and false alarm for a pseudonoise (PN) sequence code lock detector when a strong radio frequency interference (RFI) hits the communications link. A soft-limiter, a hard-limiter, and no limiter at the front-end of the receiver are considered. Both continuous wave (CW) type RFI and pulse type RFI are analyzed. It is shown that a soft-limi...