time reversal (tir) technique is an effective and simple method for data transmission in extremely multipath indoor uwb channels that mitigates the complexity of receiver by its own time focusing feature. although, tir method has the suitable performance, but it is sensitive to the non-ideal channel estimation error. in this paper at first, the bit error probability of tir-uwb communication sys...

in this paper a new uwb textile slot antenna has been designed with high precision. this work aimed to makecloser steps towards real wearability by investigating the possibilities of designing wearable uwb antenna wheretextile materials are used for the substrate as well as the conducting parts of the designed antenna. the antenna iscomposed of three textile layers: the top and bottom are condu...

this paper presents a low-cost compact planar microstrip-fed monopole antenna and its four-element array design for ultra-wideband (uwb) wireless communication and target detection applications, respectively, operating in the frequency span of 3 ghz to 11 ghz. a prototype was fabricated and then measured based on optimal parameters. the results of reflection coefficient (s11) and radiation patt...

In this paper, the performance comparison of PPM-TH, PAM-TH, and PAM-DS UWB for a single user link are analyzed for different data rates using the proposed UWB channel model from IEEE 802.15.3a. The Rake receivers with a pulse-matched filter via correlation mask are numerically evaluated with channel estimator algorithm. DS-UWB and TH-UWB with antipodal modulation perform basically the same. Ho...

Since the release by the Federal Communications Commission (FCC) of a bandwidth of 7.5GHz (from 3.1GHz to 10.6GHz) for ultra wideband (UWB) wireless communications, UWB is rapidly advancing as a high data rate wireless communication technology. As is the case in conventional wireless communication systems, an antenna also plays a very crucial role in UWB systems. However, there are more challen...

Millimeter-accuracy Ultra-Wideband (UWB) positioning systems using the Time Difference Of Arrival (TDOA) algorithm are able to be utilized in military and many other important applications. Previous research on UWB positioning system has achieved up to mm or sub-mm accuracy. However, one bottleneck in UWB system is at sampling high resolution UWB signals, as well as high resolution timing infor...

Recently, ultra-wideband (UWB) technology, which uses a very short pulse for wireless digital communications, has been extensively investigated due to its significance that enables to transmit data sequences at a very high rate. Although the propagation range of UWB signals is short (about ten meters [1]), its impact on wireless home networks can be quite significant. Apart from the support of ...

The effect of UWB interference on the DCS-1800 and GSM-900 downlink is studied for different UWB power density. For high UWB power density (-70 dBm/MHz), the effect of UWB signals is very high when the distance between UWB transmitter and DCS-1800 receiver is less than 1 m. For low UWB power density (-100 dBm/MHz), the effect of the UWB signals is quasi null even if the distance between the UWB...

In this paper, we consider the possibility of developing an optimal medium access control (MAC) layer for high data rate ultra-wideband (UWB) transmission systems that transmit minimal power. MAC in UWB wireless networks is required to coordinate channel access among competing devices. The unique UWB characteristics offer great challenges and opportunities in effective UWB MAC design. We first ...

Millimeter-accuracy Ultra-Wideband (UWB) positioning systems using the Time Difference Of Arrival (TDOA) algorithm are able to be utilized in military and many other important applications. Previous research on UWB positioning system has achieved up to mm or sub-mm accuracy. However, one bottleneck in UWB system is at sampling high resolution UWB signals, as well as high resolution timing infor...