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ABSTRACT A femto access point (FAP) is a low-cost, low-power device in-tended to be installed by a home owner, to turn the home into a tiny wireless communication cell, that operates underneath a standard cell, in licensed spectrum bands.... more
ABSTRACT A femto access point (FAP) is a low-cost, low-power device in-tended to be installed by a home owner, to turn the home into a tiny wireless communication cell, that operates underneath a standard cell, in licensed spectrum bands. Femto-cells can improve user experience in ...
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In any wireless communication environment in which a transmitter creates interference to the others, a system of non-linear equations arises. Its form (for 2 terminals) is p1=g1(p2;a1) and p2=g2(p1;a2), with p1, p2 power levels; a1, a2... more
In any wireless communication environment in which a transmitter creates interference to the others, a system of non-linear equations arises. Its form (for 2 terminals) is p1=g1(p2;a1) and p2=g2(p1;a2), with p1, p2 power levels; a1, a2 quality-of-service (QoS) targets; and g1, g2 functions akin to "interference functions" in Yates (JSAC, 13(7):1341-1348, 1995). Two fundamental questions are: (1) does the system have a solution?; and if so, (2) what is it?. (Yates, 1995) shows that IF the system has a solution, AND the "interference functions" satisfy some simple properties, a "greedy" power adjustment process will always converge to a solution. We show that, if the power-adjustment functions have similar properties to those of (Yates, 1995), and satisfy a condition of the simple form gi(1,1,...,1)<1, then the system has a unique solution that can be found iteratively. As examples, feasibility conditions for macro-diversity and multiple-connection rec...
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Abstract Recently, ultra-wide-band (UWB) technology has been approved for communi-cation applications, utilising spectrum in use by other technologies. Recent studies have evaluated the technological impact of UWB on UMTS, but not the... more
Abstract Recently, ultra-wide-band (UWB) technology has been approved for communi-cation applications, utilising spectrum in use by other technologies. Recent studies have evaluated the technological impact of UWB on UMTS, but not the corresponding economic impact. ...
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Abstract Existing regulations for ultra-wide-band technology make negligible its impact on incumbent networks. But compliant UWB devices are severely range-limited, and hence useful for a limited class of applications. More powerful UWB... more
Abstract Existing regulations for ultra-wide-band technology make negligible its impact on incumbent networks. But compliant UWB devices are severely range-limited, and hence useful for a limited class of applications. More powerful UWB devices could be allowed in ...
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Abstract The technical-economic performances of static (traditional) and auction-driven dynamic radio-spectrum allocation (FSA and DSA), and of an Utopian" federated" network (with all spectrum and customers) are compared.... more
Abstract The technical-economic performances of static (traditional) and auction-driven dynamic radio-spectrum allocation (FSA and DSA), and of an Utopian" federated" network (with all spectrum and customers) are compared. Spectrum licensees operate cellular ...
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AbstractThe Dutch auction (the price progressively falls until a buyer takes the object) is proposed as a foundation for decentralised medium-access control. Common auction formats are well-understood, relatively simple mechanism which... more
AbstractThe Dutch auction (the price progressively falls until a buyer takes the object) is proposed as a foundation for decentralised medium-access control. Common auction formats are well-understood, relatively simple mechanism which have long been used for allocating ...
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AbstractCommon auction formats are well-understood, rela-tively simple mechanism which have long been used for allocating an indivisible good to the party that values it the most, for such reasons as speed of allocation, discovery of the... more
AbstractCommon auction formats are well-understood, rela-tively simple mechanism which have long been used for allocating an indivisible good to the party that values it the most, for such reasons as speed of allocation, discovery of the true value of the object, and fraud ...
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AbstractA data terminal seeks the optimal power allocation for M sub-carriers under a general concave performance function (capacity), and a per-Watt price. The value to the terminal of one transferred information bit, as well as the... more
AbstractA data terminal seeks the optimal power allocation for M sub-carriers under a general concave performance function (capacity), and a per-Watt price. The value to the terminal of one transferred information bit, as well as the noise-normalised channel gains for each ...
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AbstractIt has long been recognised that a wireless commu-nication system can be more efficient if link-layer parameters such as modulation order are adapted to the channel conditions. The most common optimising criterion is spectral... more
AbstractIt has long been recognised that a wireless commu-nication system can be more efficient if link-layer parameters such as modulation order are adapted to the channel conditions. The most common optimising criterion is spectral efficiency (bps/Hertz) subject to very low bit-...
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ABSTRACT A femto access point (FAP) is a low-cost, low-power device in-tended to be installed by a home owner, to turn the home into a tiny wireless communication cell, that operates underneath a standard cell, in licensed spectrum bands.... more
ABSTRACT A femto access point (FAP) is a low-cost, low-power device in-tended to be installed by a home owner, to turn the home into a tiny wireless communication cell, that operates underneath a standard cell, in licensed spectrum bands. Femto-cells can improve user experience in ...
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AbstractWe allocate power to maximise social benefit in the uplink of a CDMA cell populated by data terminals, each with its own data rate, channel gain, willingness to pay (wtp), and link-layer configuration, and with energy supplies... more
AbstractWe allocate power to maximise social benefit in the uplink of a CDMA cell populated by data terminals, each with its own data rate, channel gain, willingness to pay (wtp), and link-layer configuration, and with energy supplies that are limited for some, and ...
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Abstract - The under-use of spectrum offers new perspective for a secondary usage of the spectrum. However, this can be achieved at the expense of a tight spectrum sharing control and management between the different involved parties... more
Abstract - The under-use of spectrum offers new perspective for a secondary usage of the spectrum. However, this can be achieved at the expense of a tight spectrum sharing control and management between the different involved parties (operators and users). This paper ...
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Dynamic spectrum allocation (DSA) seeks to exploit the variations in the loads of various radio-access networks to allocate the spec- trum efficiently. Previous work studies a centralised scheme in which a spectrum manager periodically... more
Dynamic spectrum allocation (DSA) seeks to exploit the variations in the loads of various radio-access networks to allocate the spec- trum efficiently. Previous work studies a centralised scheme in which a spectrum manager periodically re-allocates spectrum without business considera- tions. In the present scheme, a spectrum manager performs DSA by periodically selling to network operators short-term spectrum licenses. We target
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Research Interests: Convergence, quantum Shannon theory, Fixed Point Theory, Spread Spectrum, Power Control, and 16 moreNetwork Capacity, Decoding, Spread Spectrum Communication, GNSS receivers, Interference, Capacity, Radio Transmitters, Upper Bound, Boolean Satisfiability, Bandwidth, Electrical And Electronic Engineering, Adaptive Algorithm, Channel Capacity, Global Convergence, Radio Networks, and Uplink
AbstractWe study a cell shared by data and media trans-mitting terminals, within a model relevant to the uplink of a VSG-CDMA cell, a technique part of 3G standards. Each media terminal has a fixed data rate and an inflexible SIR... more
AbstractWe study a cell shared by data and media trans-mitting terminals, within a model relevant to the uplink of a VSG-CDMA cell, a technique part of 3G standards. Each media terminal has a fixed data rate and an inflexible SIR requirement. But the data terminals are ...
Objective: track many targets (things, animals and/or people), over known, limited area. Available resources: Well-designed network of fixed anchors (with own reliable control/coordination channel); Simple wireless device (token)... more
Objective: track many targets (things, animals and/or people), over known, limited area. Available resources: Well-designed network of fixed anchors (with own reliable control/coordination channel); Simple wireless device (token) with each target Basic operation: Anchor ...
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AbstractWe consider a generalised multi-receiver radio net-work under a quality-of-service (QoS) constraint that involves generalised carrier-to-interference ratios. This model includes as special cases many well-known schemes, such as... more
AbstractWe consider a generalised multi-receiver radio net-work under a quality-of-service (QoS) constraint that involves generalised carrier-to-interference ratios. This model includes as special cases many well-known schemes, such as those discussed by Yates (JSAC, ...
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AbstractIn any wireless communication environment in which a transmitter creates interference to the others, a system of non-linear equations arises. Its form (for 2 terminals) is p1=g1(p2;a1 ) and p2=g2(p1;a2), with p1, p2 power levels;... more
AbstractIn any wireless communication environment in which a transmitter creates interference to the others, a system of non-linear equations arises. Its form (for 2 terminals) is p1=g1(p2;a1 ) and p2=g2(p1;a2), with p1, p2 power levels; a1, a2 quality-of-service (QoS) targets; and ...
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AbstractWe analyze the optimum transmitter power levels and the optimum number of active terminals sending data to a CDMA base station. The objective is to maximize the aggregate throughput of the base station. We find that in the... more
AbstractWe analyze the optimum transmitter power levels and the optimum number of active terminals sending data to a CDMA base station. The objective is to maximize the aggregate throughput of the base station. We find that in the presence of additive noise, received power ...
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Variable spreading gain (VSG) CDMA allows data terminals to operate at dissimilar transmission rates. With this technique, the chip rate is common to all users, but the spreading gains vary. Our work is relevant to the uplink of a... more
Variable spreading gain (VSG) CDMA allows data terminals to operate at dissimilar transmission rates. With this technique, the chip rate is common to all users, but the spreading gains vary. Our work is relevant to the uplink of a single-cell VSG CDMA system, in which each ...