Cheol-Ho Shin

A Design and Performance of 4-Parallel MB-OFDM UWB Receiver

SUMMARY This paper investigates a design and performance of 4parallel MB-OFDM UWB receiver. The performance of the proposed MB-OFDM UWB receiver using a 4-parallel synchronization structure is degraded by 0.25 dB compared with that of a receiver using a 1-parallel synchronization structure in the maximum frequency/sampling clock offset tolerance in an AWGN channel. Considering other impairments, including imperfect synchronization algorithms, the effect of quantization error by the 4-parallel synchronization structure is negligible in a multi-path channel environment as well as in an AWGN channel, as identified in simulation

Packet detection scheme using cross correlation and complex multiplication in MB-OFDM UWB system

In this paper, we introduce a low power consumption packet detection scheme based on cross correlation and complex multiplication for MB-OFDM UWB system. The proposed scheme compares received signal power and calculated value explained later. The received signal is filtered by a correlator and then output of the correlator is multiplied with delayed output of the correlator and then we get the calculated value which is absolute value of output of complex multiplier. Filter tap coefficient of the correlator is given as sign value of known preamble. This scheme improves packet detection performance in multi-path fading channel model for MB-OFDM UWB system. Through the simulation for 4 block-fading channels, we describe that the proposed scheme can shrink degradation of packet detection performance due to any sampling timing offset and the fading channel model environment for MB-OFDM UWB system.

A study of detection algorithm for DAA regulation of Korea using MB-OFDM UWB receiver

This paper analyzed the performance of a detection algorithm using MB-OFDM UWB receiver based on silent time when the victim signal is received by detection limit of -80 dBm/MHz proposed in Korea for DAA. Simulation results show that the performance of the proposed detection algorithm is enough to detect the victim signal with 95% detection probability within the +/-0.5 dB error range if repeat Number over 4 is used.

Narrowband PHY design and its transmission scheme for AMI applications

This paper proposes a physical layer for advanced metering infrastructure (AMI) applications and its transmission scheme, where extremely narrowband channel is used. First, we design a narrowband physical layer transmission specification based on AMI service requirements. Then, we investigate a suitable transmission scheme, focusing on single-carrier and multi-carrier (i. e., OFDM) schemes. By discussing performance and implementation issues, we suggest a single-carrier transmission for our AMI system rather than narrowband OFDM.

An analysis of link margin for MB-OFDM UWB system in multi-path channel

This paper investigates the link margin of MB-OFDM UWB system quantitatively. Various simulations are performed considering the implementation loss by imperfect synchronization unit and the effect of multi-path fading channels. MB-OFDM UWB system uses ZP(Zero Padding) instead of CP(Cyclic Prefix) and supports two transmission modes; one is TFI(Time Frequency Interleaving) mode that transmits OFDM symbols using different carrier frequency from symbol to symbol according to Time Frequency(TF) codes, the other is FFI(Fixed Frequency Interleaving) mode that transmits OFDM symbols using a specific carrier frequency. The advantage of if and TFI is to be able to increase the transmitting power effectively compared to the existed OFDM systems that transmit the signal continuously at the same average transmitting power. From the analysis results of Ink margin, to guarantee the service range of 4m in 200Mbps mode, TFI mode must necessarily be implemented and the service range of 480Mbps mode is estimated about 1-2m in the line-of-sight multi-path channel (CMI).