Broadband Wireless Links Research Articles

Nano Antenna for Energy Harvesting

In this paper, the design & development of a Nano Antenna for Energy Harvesting is presented in a nutshell. The ever-increasing demand for energy in today's world has compelled us to seek alternative energy sources. While photovoltaic devices are being researched and developed to improve their efficiency, they can only extract energy from the visible region of the electromagnetic spectrum. Consequently, a new device called a Nano antenna has been developed that can convert thermal energy from the infrared region of the spectrum into electricity. In the near future, it is expected to contribute significantly to various fields, including space communication, broadband wireless links, wireless optical communication, mobile communication (5G), radar detection, and higher-order frequency applications. Nano antennas can be fabricated using different techniques such as electron beam lithography, focused ion beam, and nanoimprinting lithography. This paper focuses on the nanoimprinting lithography technique, as it is a cost-effective and high-throughput method. Additionally, the issue of material selection for nano antennas is a significant challenge, and the paper will discuss strategies for overcoming it. The work done & presented in this paper is the result of the mini-project work that has been done by the first sem engineering students of the college and as such there is little novelty in it and the references are being taken from various sources from the internet, the paper is being written by the students to test their writing skills in the starting of their engineering career and also to test the presentation skills during their mini-project presentation. The work done & presented in this paper is the report of the assignment / alternate assessment tool as a part and parcel of the academic assignment of the first year subject on nanotechnology & IoT.

Analogue feed‐forward carrier recovery for millimetre‐wave broadband wireless links

An analogue modulation-type independent feed-forward carrier recovery approach for broadband wireless communication systems is introduced in this work. The focus is on the deliberately increased local oscillator (LO) signal feed-through to the radio frequency (RF) port of the up-converter in a direct conversion transmitter (TX). The strong LO feed-through is used at the receiver (RX) side to demodulate the RF signal. The heart of the carrier recovery block is a narrowband bandpass filter (BPF) and a frequency divider-by-n operated in injection-locking mode to the strong LO feed-through. The proposed method is investigated through circuit level simulations; while its feasibility is examined via the successful demodulation of complex data with various modulation types up to 8 Gbps for an E-band front-end. This method can be used for transceivers working at high carrier frequencies as far as the realisation of frequency divider circuits and narrowband BPFs is technically feasible.

Design of a 300 GHz Band TWT with a Folded Waveguide Fabricated by Microelectromechanical Systems

For future broadband wireless links, we have designed a 300 GHz band traveling wave tube (TWT) with a folded waveguide fabricated by microelectromechanical systems (MEMS). The TWT operates at a beam voltage of 12 kV and a beam current of 8.3 mA. The classical large signal simulation code predicts the output power greater than 1 W and gain larger than 20 dB over the bandwidth from 280 to 300 GHz.

Broadband nanophotonic wireless links and networks using on-chip integrated plasmonic antennas.

Owing to their high capacity and flexibility, broadband wireless communications have been widely employed in radio and microwave regimes, playing indispensable roles in our daily life. Their optical analogs, however, have not been demonstrated at the nanoscale. In this paper, by exploiting plasmonic nanoantennas, we demonstrate the complete design of broadband wireless links and networks in the realm of nanophotonics. With a 100-fold enhancement in power transfer superior to previous designs as well as an ultrawide bandwidth that covers the entire telecommunication wavelength range, such broadband nanolinks and networks are expected to pave the way for future optical integrated nanocircuits.

Error and Congestion Resilient Video Streaming over Broadband Wireless

In this paper, error resilience is achieved by adaptive, application-layer rateless channel coding, which is used to protect H.264/Advanced Video Coding (AVC) codec data-partitioned videos. A packetization strategy is an effective tool to control error rates and, in the paper, source-coded data partitioning serves to allocate smaller packets to more important compressed video data. The scheme for doing this is applied to real-time streaming across a broadband wireless link. The advantages of rateless code rate adaptivity are then demonstrated in the paper. Because the data partitions of a video slice are each assigned to different network packets, in congestion-prone wireless networks the increased number of packets per slice and their size disparity may increase the packet loss rate from buffer overflows. As a form of congestion resilience, this paper recommends packet-size dependent scheduling as a relatively simple way of alleviating the buffer-overflow problem arising from data-partitioned packets. The paper also contributes an analysis of data partitioning and packet sizes as a prelude to considering scheduling regimes. The combination of adaptive channel coding and prioritized packetization for error resilience with packet-size dependent packet scheduling results in a robust streaming scheme specialized for broadband wireless and real-time streaming applications such as video conferencing, video telephony, and telemedicine.

Improved video streaming scheme for internet television with broadband wireless access

Internet television video–streaming schemes do not respond well when access is through a broadband wireless link. A simple but effective negative acknowledgment–based scheme has been designed to meet the needs of Internet television. When used with broadband wireless access, simulations show that the scheme has the better features of both raw UDP transport and the standardised Datagram Congestion Control Protocol but does not have those protocols' disadvantages. The delivered video quality is also found to be superior to multiple–connection, congestion–controlled streaming. This is important for mobile video delivery, as video quality is a key determinant of customer choice.

Channel adaptive video stream switching for broadband wireless links

This paper exploits an H.264/Advanced Video Coding codec's smooth stream switching to achieve robust video delivery across an IEEE 802.16 (WiMAX) broadband wireless link. As the wireless channel conditions vary over time, dynamic selection of bitrate and corresponding video quality will reduce the risk of harmful packet loss. The paper investigates choice of stream-switching with Secondary SP-frames or SI-frames relative to the selection of quantization parameter (QP) values. To control the switching points at the WiMAX server, the proposed scheme applies a feedback mechanism that monitors packet loss. As an additional suggestion, the paper considers an adaptive ARQ scheme to protect switching frames against packet loss. In summary, the broadband wireless streaming system gives more protection to higher quality video, reduces delay and packet loss, and improves received video quality. In particular, for the QP values selected, results show that increased quality primary-switching frames together with SI frames bring a significant gain in video quality compared with other switching schemes with secondary SP-frames. The other schemes in turn show an improvement to using `no switching' when streaming takes place over a typical WiMAX channel with burst errors. Link delay is also reduced.

Statistical Analysis of Broadband Wireless Links in Rural Areas

Third-generation (3G) cellular systems are often considered as a promising strategy for high-speed internet deployment in rural areas. However, bandwidth in 3G systems is a limited resource and can be quite different from the advertised bandwidth. In addition, in wireless applications such as voice over IP, video-conference, remote monitoring and telemetry (e.g., for healthcare applications) the Quality of Service (QoS) is critical. It is therefore important to understand how different factors affect the QoS requirements of real-time applications. Focusing on the reverse link (or uplink), we performed an assessment of the bandwidth and packet loss rate in a real network environment, using test data collected with two wireless data cards from different providers, in both rural and urban locations. The main contribution of this paper is the presentation of a formal statistical method – a Design of Experiments (DOE) analysis - that can be used to analyze the interactions between different variables, such as packet size, location, buffer size, and wireless provider. With a better understanding of the impact of such factors and their interactions, the end-user may be able to make the best selection of certain controllable parameters, in an effort to improve the QoS of the 3G connection. This is especially important for users located in rural areas, where cellular coverage is limited.