Myung Chul Park

Navigating through dynamic indoor environments using WIFI for smartphones

In recent days with a huge mass deployment of wireless networks, smartphones and various related services, different navigation techniques have been developed for indoor environments. Leveraging on these wireless networks, this paper proposes an indoor navigation model for a smartphone using WIFI. While a number of methods have been developed using received signal strength (RSS) based fingerprinting; only seldom approaches consider the dynamicity of the indoor environments. To tackle this limitation, we propose a positioning algorithm based on RSSI - fingerprinting and Manhattan distance which addresses navigation in a rapidly changing indoor environment. The model described is one of the efficient methods in terms of memory and battery consumption.

Indoor navigation using WiFi for smartphones: An improved Kalman filter based approach

This paper proposes an indoor navigation technique for a smartphone using WiFi. An improved Kalman filter (IKF) is proposed to navigate in dynamic indoor environments with the fingerprinting technique. The results indicate that the IKF shows improved accuracy when compared to the conventional Kalman filter in a real-time scenario.

Robust pedestrian dead reckoning for indoor positioning using smartphone

A scheme to improve the indoor localization by estimating heading orientation and step detection is proposed for smartphones. The accuracy can be improved with weighting factors to the accelerometer and gyroscope using the motion estimator.

Synchronization of FTN systems for UHDTV

In this paper, a pilot pattern for multicarrier faster-than-Nyquist (MFTN) signaling is proposed to get a better synchronization with reduced inter-carrier interference (ICI). The MFTN signaling is suitable for the UHDTV services by improving the spectral efficiency up to twice that of the conventional orthogonal frequency division multiplexing (OFDM). However, the MFTN scheme causes ICI which reduces the performance of synchronization. The proposed scheme reduces the ICI to improve the performance over the conventional pilot patterns.

The performance analysis for the spatial correlated MIMO systems in V2V

This paper analyzes the reception performance of the double space-time transmit diversity (DSTTD) with spatial modulation (SM) in vehicle-to-vehicle (V2V) channel. The DSTTD-SM scheme improves the performance of spectral efficiency and reception in V2V environments. The conventional multi-input multi-output (MIMO) schemes are also analyzed in the view of the antenna correlated channel and the spectral efficiency. And the simulation results shows DSTTD-SM scheme has better performance than conventional MIMO schemes in V2V channels which have Rician channel properties with correlation between transmit antennas and Doppler effects.

SM-MIMO scheme with FTN signalling for UHDTV

In this paper, a faster-than-Nyquist (FTN) based spatial modulation-multi-input multi-output (SM-MIMO) scheme is proposed to improve the channel capacity. The maximum throughput of the proposed scheme is up to twice that of the SM-MIMO scheme. It is also robust in the correlated channel environments. The proposed scheme is suitable to transmit high quality multimedia contents for UHDTV.

Analysis of Spatial Modulation MIMO Reception Performance for UHDTV Broadcasting

In this paper, the reception performance of spatial modulation multiple-output multiple-input (MIMO) is analyzed for high speed terrestrial broadcasting. The MIMO scheme is required to reduce the inter symbol interference (ISI) and spatial correlation. The spatial modulation scheme solves the problem of ISI, but the spatial correlation degrades the reception performance of SM scheme. The space-time block coded spatial modulation (STBC-SM) is combined the SM system with space-time block code (STBC) for reducing the effects of the spatial correlation. However, the STBC-SM scheme degrades the spectral efficiency by transmitting same data in the two symbol period. The double space-time transmit diversity with spatial modulation (DSTTD-SM) scheme transmits the data with full antenna combination. To adapt these SM MIMO systems into the terrestrial broadcasting system, the reception performance is analyzed using computer simulation in SUI channel environments.

A 3~5 GHz Interferer Robust IR-UWB RF Transceiver for Data Communication and RTLS Applications

This paper presents a IR-UWB(Impulse Radio Ultra-Wide Band) transceiver circuit for data communication and real time location system. The UWB receiver is designed to OOK(On-Off Keying) modulation for energy detection. The UWB pulse generator is designed by digital logic. And the Gaussian filter is adopted to reject side lobe in transmitter. The measured sensitivity of the receiver is —65 dBm at 4 GHz with 1 Mbps PRF(Pulse Repetition Frequency). And the measured energy efficiency per pulse is 20.6 pJ/bit. The current consumption of the receiver and transmitter including DA is 27.5 mA and 25.5 mA, respectively, at 1.8 V supply.