introduction: pulmonary tuberculosis is major problem worldwide and it is estimated one third the world population are already infected and each year 9 million people develop full blown tuberculosis of these 3 million die of the disease, annually. delay in diagnosis and treatment are major problems that play a significant role in all aspect of the disease from patient treatment to transmission ...

Direct-sequence code-division multiple-access (DS-CDMA) signals are often regarded as a result of the multiplication of the data bits by a spreading sequence, clocked at a higher rate than the data sequence (where the factor of the rates is the spreading factor), cf. figure 1 a. A conceptually different, but equivalent, description is that the symbol rate is raised by up-sampling (repetition en...

Non Wide Sense Stationary Uncorrelated Scattering (Non-WSSUS) is one of characteristics for high-speed railway wireless channels. In this paper, estimation of Non-WSSUS Channel for OFDM Systems is considered by using Compressive Sensing (CS) method. Given sufficiently wide transmission bandwidth, wireless channels encountered here tend to exhibit a sparse multipath structure. Then a sparse Non-...

RF channel measurements in underground mines have important applications in the field of mobile communications for improving operational efficiency and worker safety. This paper presents an experimental study of the ultra wideband (UWB) radio channel, based on extensive sounding campaigns covering the underground mine environment. Measurements were carried out in the frequency band of 2–5 GHz. ...

The traditional analog signal processing is expected to progressively substituted by the processing times of the digital domain in the VLSI .Within this novel paradigm ,digitally controlled delay lines should play the vital role in the digital-toanalog converters ,and in analog intensive circuits. From a practical point of view, nowadays, DCDL is a key block in the many applications like All Di...

Cyclic Delay Diversity (CDD) is a simple and efficient space-time diversity technique. It can be used in OFDM and DFT-Spread-OFDM. The traditional CDD has low complexity and system overhead, however, also has some limitations on performance and is sensitive to propagation environment. In this paper, two improved CDD scheme including open-loop and closeloop strategies for uplink and downlink of ...

The optimal arrival-time distribution that maximizes the delay-capture probability in spread-spectrum packet radio networks is derived. It is shown that using the optimal arrival-time distribution, the capture probability converges to a finite value as the number of contending users increase. Normalized throughput and average delay is computed for slotted ALOHA random access packet radio networ...

Traditionally, diffused infrared configuration has been studied with the assumption that the illuminated region is placed at room ceiling. This is done to ensure minimum path loss to a maximum number of receiver locations. In many practical situations, this arrangement might be difficult to implement, either due to the ceiling structure or the difficulty in illuminating the entire ceiling unifo...

This paper presents the measured propagation characteristics like a path loss, delay spread and angular spread for urban environments in Jeju at 781 MHz. Measurements were made with a wide band MIMO channel sounder using a pseudo noise (PN) mode, 50 Mcps, 20 ns resolution and 40.96 μs maximum delay. Base station (BS) antenna height of 5 m was tested with a mobile station (MS) antenna height of ...

This paper studies the impact of surrounding buildings on path loss and multipath delay spread for Personal Communication Services (PCS) operating inside of buildings. Measurements conducted inside three large office buildings in the San Francisco Bay area provide an extensive database for propagation models at 915 MHz and 1900 Wlz, and show variability in path loss and delay spread caused by m...