31 research outputs found

    Bluetooth/WLAN receiver design methodology and IC implementations

    Get PDF
    Emerging technologies such as Bluetooth and 802.11b (Wi-Fi) have fuelled the growth of the short-range communication industry. Bluetooth, the leading WPAN (wireless personal area network) technology, was designed primarily for cable replacement applications. The first generation Bluetooth products are focused on providing low-cost radio connections among personal electronic devices. In the WLAN (wireless local area network) arena, Wi-Fi appears to be the superior product. Wi-Fi is designed for high speed internet access, with higher radio power and longer distances. Both technologies use the same 2.4GHz ISM band. The differences between Bluetooth and Wi-Fi standard features lead to a natural partitioning of applications. Nowadays, many electronics devices such as laptops and PDAs, support both Bluetooth and Wi-Fi standards to cover a wider range of applications. The cost of supporting both standards, however, is a major concern. Therefore, a dual-mode transceiver is essential to keep the size and cost of such system transceivers at a minimum. A fully integrated low-IF Bluetooth receiver is designed and implemented in a low cost, main stream 0.35um CMOS technology. The system includes the RF front end, frequency synthesizer and baseband blocks. It has -82dBm sensitivity and draws 65mA current. This project involved 6 Ph.D. students and I was in charge of the design of the channel selection complex filter is designed. In the Bluetooth transmitter, a frequency modulator with fine frequency steps is needed to generate the GFSK signal that has +/-160kHz frequency deviation. A low power ROM-less direct digital frequency synthesizer (DDFS) is designed to implement the frequency modulation. The DDFS can be used for any frequency or phase modulation communication systems that require fast frequency switching with fine frequency steps. Another contribution is the implementation of a dual-mode 802.11b/Bluetooth receiver in IBM 0.25um BiCMOS process. Direct-conversion architecture was used for both standards to achieve maximum level of integration and block sharing. I was honored to lead the efforts of 7 Ph.D. students in this project. I was responsible for system level design as well as the design of the variable gain amplifier. The receiver chip consumes 45.6/41.3mA and the sensitivity is -86/-91dBm

    Expressed and Silent Carbapenemase Genes Detected by Multiplex PCR in both Carbapenem- Resistant and Phenotypically-Susceptible Gram Negative Bacilli

    Get PDF
    Introduction: Carbapenemase-producing Gram-negative bacilli have been major culprits in hospital-associated infections (HAIs), particularly in critically ill patients suffering device-associated infections (DAIs). The current study aimed to investigate the performance of the modified Hodge test (MHT) as a phenotypic confirmatory method for the detection of carbapenemase-producing Gram-negative bacilli and to compare it to the gold standard PCR for the detection of carbapenemase production in both non-susceptible and phenotypically susceptible isolates. The latter were expected to harbor silent carbapenemase genes, as suspected from the inappropriate response to carbapenem therapy. Methods: Ninety-five bacterial isolates from 75 critically ill patients were collected over 6 months from several ICUs at Cairo University Hospitals. The isolates were subjected to antibiotic susceptibility testing (AST) for carbapenems and were further screened by MHT, followed by genotypic analysis via multiplex PCR. Results: Enterobacteriaceae were the most commonly isolated pathogens (55.8% of the total isolates), followed by Acinetobacter spp. (24%). Lower respiratory tract infections were the most common HAIs (42.11%), followed by surgical site infections (27.37%). All isolates demonstrating carbapenem resistance by AST were found to harbor at least one of the following carbapenemase genes: blaKPC, blaOXA-48, blaIPM, blaVIM, and blaNDM-1. Alarmingly, 97.8% of the isolates which exhibited carbapenem-susceptible profile and negative MHT were harboring carbapenemase genes as confirmed by multiplex PCR. With the exception of one isolate (E. coli) which was not harboring any carbapenemase gene, the remaining 94 bacterial isolates were found to carry either a single or multiple carbapenemase genes. Conclusion: The silent dissemination of different classes of carbapenemases even in isolates with negative MHT is a daunting challenge. It necessitates the implementation of strict antibiotic stewardship along with updated and actionable approach to detect non-expressed carbapenemase genes in phenotypically susceptible isolates

    High incidence of asymptomatic cases during an outbreak of Plasmodium malariae in a remote village of Malaysian Borneo

    Get PDF
    An outbreak of Plasmodium malariae occurred in Sonsogon Paliu village in the remote area of Ulu Bengkoka sub-district of Kota Marudu, Northern Sabah, Malaysian Borneo from July through August 2019. This was the first outbreak of malaria in this village since 2014. On 11th July 2019 the Kota Kinabalu Public Health Laboratory notified the Kota Marudu District Health Office of a Polymerase Chain Reaction (PCR) positive case of P. malariae. This index case was a male from Sulawesi, Indonesia working for a logging company operating in Sonsogon Paliu. During the resulting outbreak, a total of 14 symptomatic cases were detected. All of these cases were positive by thick and thin blood smear examination, and also by PCR. During the outbreak, a mass blood survey screening was performed by light-microscopy and PCR. A total of 94 asymptomatic villagers 31 (33.0%) were PCR positive but thick and thin blood smear negative for P. malariae. Both symptomatic and asymptomatic cases received treatment at the district hospital. When symptomatic and asymptomatic cases were considered together, males (29/45. 64.5%) were infected more than females (16/45, 35.6%), the male:female ratio being 1.8:1. Adults were the predominant age group infected (22/45, 48.9%) followed by adolescents (19/45, 42.2%) and children under five years of age (4/45, 8.9%). This report illustrates that symptomatic and submicroscopic cases pose a challenge during P. malariae outbreaks and that PCR is a valuable tool for their identification. The rapid identification and control of imported malaria is crucial for the continued control of malaria in Malaysia

    High frequency communication and sensing : traveling-wave techniques

    No full text

    High Frequency Communication and Sensing

    No full text

    A single-ended CMOS sensing circuit for MEMS gyroscope with noise cancellation

    No full text
    [abstract not available
    corecore