931 resultados para Broadband antennas
Resumo:
This paper presents a deterministic modelling approach to predict diffraction loss for an innovative Multi-User-Single-Antenna (MUSA) MIMO technology, proposed for rural Australian environments. In order to calculate diffraction loss, six receivers have been considered around an access point in a selected rural environment. Generated terrain profiles for six receivers are presented in this paper. Simulation results using classical diffraction models and diffraction theory are also presented by accounting the rural Australian terrain data. Results show that in an area of 900 m by 900 m surrounding the receivers, path loss due to diffraction can range between 5 dB and 35 dB. Diffraction loss maps can contribute to determine the optimal location for receivers of MUSA-MIMO systems in rural areas.
Resumo:
Innovation is vital for the future of Australia.s internet economy. Innovations rely on businesses. ability to innovate. Businesses. ability to innovate relies on their employees. The more these individual end users engage in the internet economy, the better businesses. engagement will be. The less these individual end users engage, the less likely a business is to engage and innovate. This means, for the internet economy to function at its fullest potential, it is essential that individual Australians have the capacity to engage with it and participate in it. The Australian federal government is working to facilitate the internet economy through policies, legislation and practices that implement high-speed broadband. The National Broadband Network will be a vital tool for Australia.s internet economy. Its .chief importance¡® is that it will provide faster internet access speeds that will facilitate access to internet services and content. However, an appropriate infrastructure and internet speed is only part of the picture. As the Organisation for Economic Co-operation and Development identified, appropriate government policies are also needed to ensure that vital services are more accessible by consumers. The thesis identifies essential theories and principles underpinning the internet economy and from which the concept of connectedness is developed. Connectedness is defined as the ability of end users to connect with internet content and services, other individuals and organisations, and government. That is, their ability to operate in the internet economy. The NBN will be vital in ensuring connectedness into the future. What is not currently addressed by existing access regimes is how to facilitate end user access capacity and participation. The thesis concludes by making recommendations to the federal government as to what the governing principles of the Australian internet economy should include in order to enable individual end user access capacity.
Resumo:
In this article I would like to examine the promise and possibilities of music, digital media and National Broadband Network. I will do this based on concepts that have emerged from a study undertaken by Professor Andrew Brown and I that categorise technologies into what we term representational technologies and technologies with agency
Resumo:
A tunable decoupling and matching network (DMN) for a closely spaced two-element antenna array is presented. The DMN achieves perfect matching for the eigenmodes of the array and thus simultaneously isolates and matches the system ports while keeping the circuit small. Arrays of closely spaced wire and microstrip monopole pairs are used to demonstrate the proposed DMN. It is found that monopoles with different lengths can be used for the design frequency by using this DMN, which increases the design flexibility. This property also enables frequency tuning using the DMN only without having to change the length of the antennas. The proposed DMN uses only one varactor to achieve a tuning range of 18.8% with both return loss and isolation better than 10-dB when the spacing between the antenna is 0.05λ. When the spacing increases to 0.1λ, the simulated tuning range is more than 60%.
Resumo:
It is important to try to come to grips with what content and applications are likely to be feasible, popular and beneficial on the National Broadband Network, which is being rolled out now. This short article looks at the three main types of content ('unmanaged', 'managed' and 'publicly supported' services), shows how creative content is being, or could be, deployed across all three, and discusses the policy opportunities and challenges for content industries in connecting with what Minister for Regional Australia, Regional Development and Local Government and Minister for the Arts Simon Crean calls 'the largest cultural infrastructure project Australia has ever seen'.
Resumo:
This paper addresses the problem of degradations in adaptive digital beam-forming (DBF) systems caused by mutual coupling between array elements. The focus is on compact arrays with reduced element spacing and, hence, strongly coupled elements. Deviations in the radiation patterns of coupled and (theoretically) uncoupled elements can be compensated for by weight-adjustments in DBF, but SNR degradation due to impedance mismatches cannot be compensated for via signal processing techniques. It is shown that this problem can be overcome via the implementation of a RF-decoupling-network. SNR enhancement is achieved at the cost of a reduced frequency bandwidth and an increased sensitivity to dissipative losses in the antenna and matching network structure.
Concerns about the rollout of broadband : a legal consideration of Australia’s NBN greenfield policy
Resumo:
This paper examines the Australian federal government’s proposal that developers take the primary role for deploying the National Broadband Network (‘NBN’) in greenfield estates. It identifies issues facing the NBN’s implementation and concerns raised by industry. A failure to address these concerns may lessen industry support as well as adversely impact on consumers as NBN implementation costs are passed onto them. The author identifies the need for NBN legislation to clearly establish what is a ‘greenfield estate’; how and when exemptions from implementation obligations will apply; and that NBN services must be treated the same as any other utility service.
Resumo:
The Australian government, and opposition, are committed to facilitating high-speed broadband provision. In April 2009 the (then) Labor government announced a proposal to facilitate provision by mandating “…the use of fibre optic infrastructure … in greenfield estates ….” Separately, the installation of (usually overhead) cables commenced in select brownfield areas throughout Australia. In the lead up to the 2010 federal election, the broadband policy focus of the (then) federal opposition was to enabling private investment rather than direct investment by government itself. High-speed broadband is essential for Australia’s economic future. Whether implementation is undertaken by government, government owned corporations or private investors, will impact on the processes to be followed. Who does what, also will determine the rights available to land owners. The next stage, of necessity, will involve the establishment of procedures to require the retrofitting of existing urban environments. This clearly will have major property, property rights and valuation impacts. As Horan (2000) observed “…preserving... unique characteristics … of…regions requires a compromise between economic ambitions and social, cultural, and environmental values”. The uncertainty following the federal election, and the influence of independants with individual agendas; presents unique challenges for broadband implementation. This paper seeks to identify the processes to be followed by various potential broadband investors as they work to establish a ubiquitous network. It overviews current legislative regimes and examines concerns raised by stakeholders in various government reviews. It concludes by plotting a clear way forward to the future, with particular regard to property rights and usage.
Resumo:
Just as telecommunications has played a key role in the global economy,1 high-speed broadband will have a significant role to play in the future of the digital economy. In particular high-speed broadband will have a role to play in the delivery of applications and services necessary for acquiring, and maintaining into the future Australia and Australians’ appropriate education level; community; health services, information provision and support; government services and engagement and participation by the public in the political process.
Resumo:
A practical method for the design of dual-band decoupling and matching networks (DMN) for two closely spaced antennas using discrete components is presented. The DMN reduces the port-to-port coupling and enhances the diversity of the antennas. By applying the DMN, the radiation efficiency can also be improved when one port is fed and the other port is match terminated. The proposed DMN works at two frequencies simultaneously without the need for any switch. As a proof of concept, a dual-band DMN for a pair of monopoles spaced 0.05λ apart is designed. The measured return loss and port isolation exceed 10 dB from 1.71 GHz to 1.76 GHz and from 2.27 GHz to 2.32 GHz.
Resumo:
Constant development of new wireless standards increases the demand for more radiating elements in compact end-user platforms. A decrease in antenna separation gives rise to increased antenna coupling, resulting in a reduction of the signal-to-interference-plus-noise-ratio (SINR) between transmitter and receiver. This paper proposes a decoupling network which provides dual band port isolation for a pair of distinct antennas. A prototype has been fabricated to verify the theory.
Resumo:
The paper seeks to clarify the role of Local Government Authorities in facilitating the Australian digital economy. It does this by analysing responses to the 2012 BTA, NBN and Digital Economy Survey. This reveals the level of recognition by LGAs of relevant issues; their level of use of federal, state and other programs designed to enable end user engagement; and other actions LGAs are undertaking to enable their regional digital economies. The analysis reinforces the significant role of LGAs in the future of Australia’s digital economy and identifies areas where assistance may be required.