Young Joon Song

Frame synchronization word in W-CDMA system

This letter presents a set of sequences of length 15 called frame synchronization words in wideband code-division multiple-access (W-CDMA) system. They all have two-valued ideal auto-correlation property. And the correlation function between a preferred pair of sequences shows also two-valued cross-correlation property with minus peak at the middle shift and lowest out-of-phase cross-correlation value of 1. Since the length of the sequences is equal to the number of slots per frame, they are suitable for slot-by-slot and double-check frame synchronization confirmation. We discuss the realization circuit for the generation of frame synchronization words by using the concept of preferred pairs of frame synchronization words, complementary mapping relationship, and maximal length sequence.

Reconstruction of BCH codes using probability compensation

If a receiver does not have accurate channel coding parameters, it becomes difficult to decode digitized encoding bits correctly from a noisy intercepted bit stream. To perform decoding without the channel coding information, we should estimate the channel coding parameters and identify the channel coding type. In this study, we propose an efficient algorithm for the reconstruction of the BCH (Bose-Chaudhuri-Hocquenghem) code. We use the property of cyclic codes for the reconstruction of the BCH code. In addition, we present a probability compensation method to improve the reconstruction performance. This is based on the concept that a random data pattern can also be divisible by a minimal polynomial of the generator polynomial of the BCH code. We use this property to improve the recognition performance, and we confirm the performance improvement through an intensive computer simulation.

Optimal frame synchronization property of pilot bit pattern in compressed mode

This paper shows the frame synchronization word (FSW) of pilot bit pattern in 3GPP (3/sup rd/ generation partnership project) W-CDMA (wideband code division multiple access) system are designed to have optimal frame synchronization property in compressed mode using complementary relationship between preferred pair of FSWs.

Frame synchronization confirmation technique using pilot pattern in W-CDMA system

This paper proposes a new frame synchronization confirmation technique using a new pilot pattern in a W-CDMA (wideband code division multiple access) system. By applying the proposed technique for autocorrelation functions of the pilot patterns in a W-CDMA system, we can obtain a side-lobe cancellation effect except middle shift. It is also shown that the pilot pattern in a W-CDMA system is appropriate for frame synchronization confirmation through computer simulation.

SSDT cell ID codes for W-CDMA system

The code division multiple access (CDMA) system capacity is limited by the amount of interference of the system. To reduce the unnecessary interference, this paper proposes optimized cell identification (ID) codes for site selection diversity transmission (SSDT) power control in wideband code division multiple access system of third generation partnership project (3GPP). In order to select a primary cell, each cell is assigned a temporary identification (ID) and user equipment (UE) periodically informs a primary cell ID to the connecting cells during soft handover. The non-primary cells selected by UE do not transmit the dedicated physical data channel (DPDCH) to reduce the interference. A major issue with the SSDT technology is the impact of uplink symbol errors on its performance. These errors can corrupt the primary ID code and this may lead to wrong decoding in the base station receivers. The proposed SSDT cell ID codes are designed to minimize the problem and to be easily decoded using simple fast Hadamard transformation (FHT) decoder.

Design of binary sequences with optimal frame synchronization property

Based on the ideal autocorrelation property of sequences with odd length n, a general method to generate binary sequences of length N=2n with optimal frame synchronization property is studied. The sequence generation method may be useful in the field of communication systems.