Analysis and Performance Comparison of DVB-T and DTMB Systems for Terrestrial Digital TV

Orthogonal frequency-division multiplexing (OFDM) is the most popular transmission technology in digital terrestrial broadcasting (DTTB), adopted by many DTTB standards. In this paper, the bit error rate (BER) performance of two DTTB systems, namely cyclic prefix OFDM (CP-OFDM) based DVB-T and time domain synchronous OFDM (TDS-OFDM) based DTMB, is evaluated in different channel conditions. Spectrum utilization and power efficiency are also discussed to demonstrate the transmission overhead of both systems. Simulation results show that the performances of the two systems are much close. Given the same ratio of guard interval (GI), the DVB-T outperforms DTMB in terms of signal to noise ratio (SNR) in Gaussian and Ricean channels, while DTMB behaves better performance in Rayleigh channel in higher code rates and higher orders of constellation thanks to its efficient channel coding and interleaving scheme

Performance of the MIMO CS-PRP-OFDM Systems with Complementary Codes

Proposed new scheme for ST-BC MIMO-OFDM systems,[[abstract]]This paper presents a new transceiver framework of the MIMO-OFDM systems, with the space-time block code (STBC). Unlike the conventional Pseudo-Random Postfix (PRP) - OFDM in our proposed framework the null samples of zero-padding (ZP)-OFDM is replaced by known cyclic postfix sequence (CPS), weighted by a pseudo-random (PR) scalar. Since the CPS is implemented by the cyclic-shift (CS) complementary code (CC) sequences, the proposed transceiver scheme is referred to as the MIMO CS-PRP-OFDM systems. By exploring the useful property of CC sequences, convolved with channel formation, the receiver design associated with the semi-blind channel estimation of the proposed MIMO CS-PRP-OFDM systems is affected only by the background noise. It avoids the interference of the transmitted signals, and yields achieving better system performance, in terms of symbol error rate, compared with the conventional PRP-OFDM based systems, with less complexity. This is especially true when the signal-to-noise ratio is increased.[[incitationindex]]EI[[conferencetype]]國際[[conferencedate]]20111207~20111209[[conferencelocation]]Chiang Mai, Thailan

Performance of the MIMO PRCP-OFDM System with Orthogonal Cyclic-Shift Sequences

[[abstract]]Unlike the conventional Pseudo-Random Posfix (PRP) orthogonal frequency division multiplexing (OFDM) or PRP-OFDM approach, recently we proposed a new transceiver framework for OFDM system, named as the Pseudo Random Cyclic Postfix (PRCP)-OFDM, with complementary codes (CC). Also, it wa MIMO PRCP-OFDM system the performance is investis extended to the multiple-input multiple-output (MIMO) antennas system, equipped with the space-time block code (SP-BC). In this paper, the cyclic postfix (CP) sequence is implemented with the Orthogonal Cyclic-shift (OCS) sequences to substitute the CC. By exploring the useful property of OCS sequences, convolved with channel information, at receiver side it can be employed to perform semi-blind channel estimation without incurring the signal interference to the desired postfix sequences. It is affected only by the background noise, and yields achieving better system performance. To demonstrate the merits of proposed ST-BCgated and further compared with the ST-BC MIMO PRP-OFDM system and ST-BC MIMO CP-OFDM system with optimal training pilots, under various channel environments.[[sponsorship]]ISPACS[[incitationindex]]EI[[conferencetype]]國際[[conferencedate]]20121104~20121107[[booktype]]電子版[[iscallforpapers]]Y[[conferencelocation]]Tamsui, Taiwa

Classical and Bayesian Linear Data Estimators for Unique Word OFDM

Unique word - orthogonal frequency division multiplexing (UW-OFDM) is a novel OFDM signaling concept, where the guard interval is built of a deterministic sequence - the so-called unique word - instead of the conventional random cyclic prefix. In contrast to previous attempts with deterministic sequences in the guard interval the addressed UW-OFDM signaling approach introduces correlations between the subcarrier symbols, which can be exploited by the receiver in order to improve the bit error ratio performance. In this paper we develop several linear data estimators specifically designed for UW-OFDM, some based on classical and some based on Bayesian estimation theory. Furthermore, we derive complexity optimized versions of these estimators, and we study their individual complex multiplication count in detail. Finally, we evaluate the estimators' performance for the additive white Gaussian noise channel as well as for selected indoor multipath channel scenarios.Comment: Preprint, 13 page