Maximising Signal Strength inside Buildings for Wireless Lan Systems Using Ofdm
نویسندگان
چکیده
Propagation inside buildings suffer from large shadowing and high multipath effects. This is a serious problem for Wireless Local Area Network (WLAN) systems. OFDM has a high multipath tolerance and this paper shows how this can be used to overcome the problems due to shadowing. OFDM allows a base station to transmit and receive the same signal at the same frequency from multiple locations, at a low cost and without detrimental effects of Inter-Symbol Interference (ISI). The reduced shadowing and path loss allows: an increased system capacity for such a multi-transeiver WLAN cell, or a decrease in intercellular interference in a cellular WLAN.
منابع مشابه
Smart Random Channel Access in OFDM Systems by Joint Signal Processing and Packet Scheduling
Wireless LAN and many other wireless communication systems have applied OFDM to mitigate multipath. Considering that the requirement of random access may reduce performance due to contentions, in this paper we show that OFDM techniques can assist random access contention resolution. A method is proposed with both OFDMbased physical layer signal processing and MAC layer packet scheduling. It is ...
متن کاملA Software System for Locating Mobile Users: Design, Evaluation, and Lessons
We have built a software system, RADAR, to locate mobile users connected to an in-building radiofrequency (RF) wireless LAN. RADAR uses signal strength information extracted from the wireless network interface, in conjunction with a Radio Map of the building, to determine location. Over the past year we have deployed this system in multiple buildings on our campus using two different wireless L...
متن کاملOrientation Estimation Method Using Divergence of Signal Strength Distribution
Over the last few years, many positioning systems using wireless LAN have been developed. Some systems use signal strength for positioning. But the distribution of received signal strength depends on orientation of mobile terminal. In this paper, we examine the differences of received signal strength distribution to each orientation and propose an orientation estimation method using the diverge...
متن کاملAnalysis and Comparison of PAPR Reduction Techniques in OFDM Systems
The destructive impact of fading environments and also bandwidth limitations are two main challenges which communication is dealing with them. These challenges can affect on the growth of wireless communication and even cause reliable communications and high data rate to be prevented. Thus, OFDM (Orthogonal Frequency Division Multiplexing) modulation by using of fast calculation hardwares such ...
متن کاملIncreasing the Performance of OFDM Systems by PAPR Reduction in PTS Technique using Election Optimization Algorithm
Orthogonal Frequency Division Multiplexing (OFDM) is a useful technology in wireless communications that provides high-rate data transmission in multipath fading channels. The advantages of OFDM systems are the high spectral efficiency and strong resistance to frequency selective fading. In OFDM systems, a large number of sub-carriers are used to modulate the symbols causing the time-domain OFD...
متن کامل