Showing papers on "Cognitive radio published in 2001"

Cognitive radio for flexible mobile multimedia communications

Abstract: Wireless multimedia applications require significant bandwidth, some of which will be provided by third-generation (3G) services. even with substantial investment in 3G infrastructure, the radio spectrum allocated to 3G will be limited. Cognitive radio offers a mechanism for the flexible pooling of radio spectrum using a new class of protocols called formal radio etiquettes. This approach could expand the bandwidth available for conventional uses (e.g., police, fire and rescue) and extend the spatial coverage of 3G in a novel way. Cognitive radio is a particular extension of software radio that employs model-based reasoning about users, multimedia content, and communications context. This paper characterizes the potential contributions of cognitive radio to spectrum pooling and outlines an initial framework for formal radio-etiquette protocols.

Ultra-Wideband Technology for Short- or Medium-Range Wireless Communications

Abstract: Ultra-Wideband (UWB) technology is loosely defined as any wireless transmission scheme that occupies a bandwidth of more than 25% of a center frequency, or more than 1.5GHz. The Federal Communications Commission (FCC) is currently working on setting emissions limits that would allow UWB communication systems to be deployed on an unlicensed basis following the Part 15.209 rules for radiated emissions of intentional radiators, the same rules governing the radiated emissions from home computers, for example. This rule change would allow UWB-enabled devices to overlay existing narrowband systems, which is currently not allowed, and result in a much more efficient use of the available spectrum. Devices could, in essence, fill in the unused portions of the frequency spectrum in any particular location. These recent developments by the FCC give Intel a unique opportunity to develop equipment that could potentially take advantage of the vast amount of usable spectrum that exists in the wireless space, and that could provide an engine to drive the future high-rate applications that are being conceived throughout this industry. Intel Architecture Labs (IAL) is currently researching UWB technology in order to better understand its benefits, limitations, and technical challenges when used for high-rate communications. This paper introduces the reader to this technology, from potential applications to regulatory hurdles, to possible implementations and future challenges.

Intelligent control of radio resources in a wireless network

Abstract: A method of controlling radio resources in a cellular wireless network comprising a plurality of fixed antennas providing overlapping radio coverage, the method comprising dynamically adjusting the radiation patterns of the antennas using co-ordinated distributed control to optimise capacity. The wireless network may be a cellular mobile network or part thereof comprising a plurality of cells, each cell having a base station comprising an antenna, and the method may then further comprise determining the concentration of mobile stations in each cell and changing the radiation/reception pattern of the antennas of some or all of the base stations in response to the concentration of mobile stations in each cell.

Triggered packet data rate change in a communication system

Abstract: Communication traffic associated with one or more mobile terminals is monitored to efficiently manage allocated radio resources. A rate management technique dynamically adjusts allocated radio resources to increase or decrease the data rate capacity of allocated radio channels based on actual channel usage. In this manner, radio resources are more efficiently utilized because the amount of excess capacity allocated to individual subscribers is reduced. Monitoring communication traffic may also be used to determine whether additional radio channel resources are allocated to a given subscriber. For example, in a cdma2000 radio access network, subscribers are typically allocated fundamental radio channels and then assigned supplemental channels to access higher data rate services. By monitoring fundament channel traffic characteristics, such as the queue length or packet size of outgoing packet data, the radio access network can determine whether supplemental channel allocation is warranted.

Broadband fixed wireless access as a key component of the future integrated communications environment

Abstract: It is an exciting time for broadband fixed wireless with key developments in frequency bands from 1 to 60 GHz and a range of new technologies being developed. While working on these new technologies, it is easy to forget that fixed wireless access will form part of an integrated communications environment of the future where users will have one communications device working in the home, at the office, and outdoors. This article predicts the communications environment of the next 20 years and looks at the role of fixed access within that environment. This involves assessing how fixed access systems will interface and integrate with in-home wireless networks, how their architecture will enable multiservice operators to utilize the same core network across a range of different access technologies, and how they will act as a channel to carry mobile traffic originating within the building. Based on the requirements this vision and architecture implies, this article critically assesses the different fixed wireless technologies available to date and compares their capabilities to provide future-proof broadband fixed wireless platforms.

Method and apparatus for determining a location of a mobile radio

Abstract: Cell coordinates available in the radio network is used to determine an area where the mobile radio is located and does not rely upon mobile radio measurements. Such cell coordinates for cells currently associated with the mobile radio are used by the radio network to determine a location of the mobile radio. Those current cells may include cells that are candidates for supporting a communication with the mobile radio, an active set of cells, cells that are currently supporting communication with the mobile radio, or some other set of cells geographically associated with the mobile radio.

Radio communication control station, radio communication terminal, home agent, and radio communication method

Abstract: A radio communication control station including a packet receiver, a paging controller, a location information receiver, and a retriever. The packet receiver receives an IP packet destined for a radio communication terminal subscribing to one of sub-networks constituting a composite radio communication network. The paging controller causes one of the sub-networks to page the radio communication terminal. The location information receiver receives location information on a current location of the radio communication terminal from the radio communication terminal. The retriever retrieves candidates of sub-networks that can be employed by the radio communication terminal on the basis of the location information on the radio communication terminal. The radio communication terminal selects a sub-network for its use among from the candidates and establishes an environment for communication with the sub-network.

Wireless local area network using impulse radio technology to improve communications between mobile nodes and access points

Abstract: A wireless local area network is provided that uses impulse radio technology to improve communications between a mobile node and access point. In one embodiment of the present invention, a wireless network, a mobile node and a method are provided that use the communication capabilities of impulse radio technology to overcome the problematical “dead zones” and “multipath interference” associated with a traditional wireless LAN. In another embodiment of the present invention, a wireless network, a mobile node and a method are provided that have an improved roaming scheme due to the use of the positioning and tracking capabilities of impulse radio technology. These embodiments and several other embodiments of the present invention are described herein.

Power control in radio system

Abstract: A radio system comprising one or more network parts and one or more terminals in radio connection to the network part, radio traffic on the radio connection between the network part and the terminal being transmitted in a frame, the network part being arranged to allocate downlink transmission power in at least two timeslots to a given terminal from timeslots determined by said frame. The network part of the radio system is arranged to produce the transmission power of a transmission to a terminal timeslot-specifically such that the power ratio of the transmission power of a radio transmission to the terminal in each timeslot and the interference power caused by transmissions to other terminals exceeds a threshold value preset on the power ratio in the timeslot.

Software defined radio and radio system

Abstract: In order to provide a software defined radio and an approval system of a radio which can flexibly cope with specification alteration, a software defined radio includes a storage for holding transmission and reception characteristic information serving as a specification criterion; and a control unit for comparing a measured value obtained from a measurement circuit with the information of the specification criterion and conducting setting of the radio so as to satisfy the specification.

Method and apparatus for organizing and scheduling multimedia data transfers over a wireless channel

Abstract: A radio frequency communications system ( 100 ) includes wireless terminals ( 102 ) and base sites ( 104 ). The wireless terminals communicate with the base sites over a radio frequency channel ( 106 ). The base sites are interconnected to each other and other network elements via a packet network. The communication system has a radio frequency channel ( 400 ) with time slots ( 406, 408 ) for transmission of both delay-sensitive data, such as streaming audio and video, and non-delay-sensitive data. A method and apparatus are provided for determining whether a time slot in the radio frequency channel is to be allocated to delay-sensitive data or non-delay-sensitive data ( 704, 706, 708 ). Each packet of data transmitted over the wireless channel has a type of service field ( 900 ). The type of service field has a precedence or priority value ( 902 ) and a service type ( 904 ). The priority values are used to determine which packet should be transmitted across the radio frequency channel next and the service type determines the transmission protocol.

Method for selection of radio network, as well as system and terminal utilizing the method

Abstract: The present invention relates to a method for selection of radio network when a terminal is allowed to select between a plurality of accessible radio networks. The terminal places the accessible radio networks in order of precedence and connects to the radio network which has been allocated highest priority. The radio networks are allowed to be of different kind, such as GSM, GPRS, WLAN etc. The terminal is allowed to communicate with the different radio network at which a priority list defines an order of preference between the networks. Selection of network is made by means of the priority list. When the terminal loses contact with the selected radio network the terminal checks whether contact with other radio network can be established. Further is checked whether network with higher priority than the utilized one is accessible. Connection is after that made to a network that has highest priority among the accessible networks.

Method and apparatus for determining and reserving bandwidth for transmitting delay-sensitive streaming data over a radio frequency channel

Abstract: A radio frequency communications system ( 100 ) includes wireless terminals ( 102 ) and base sites ( 104 ). The wireless terminals communicate with the base sites over a radio frequency channel ( 106 ). The base sites are interconnected to each other and other network elements via a packet network. A method and apparatus determine for a particular delay-sensitive application on the wireless terminal, for example, an audio or video transmission, the requirements for bandwidth for transmission over the radio frequency channel ( 500, 502 ). After the requirements on the radio frequency channel are determined, the necessary channel bandwidth, if available, is reserved or allocated to guarantee performance to the application ( 510 ). The reserved bandwidth is utilized by selectively granting access to the radio frequency channel on the basis of the bandwidth allocated to the device.

Authenticating method for short-distance radio devices and a short-distance radio device

Abstract: The invention provides a method for making mutual authentication between short-distance radio devices automatically or after confirmation by users, and a short-distance radio device for realizing the method. In a condition where a plurality of radio devices exist, each of the radio devices comprising a data communicating unit for performing short-distance radio communication and an authenticating unit for performing authentication of the radio device, the authenticating unit performs mutual authentication between two radio devices automatically or after confirmation by users of the radio devices when the two radio devices come closer to each other to such an extent that coverage areas of radio waves generated by the radio devices overlap with each other.

Wireless transmission method and wireless transmission apparatus

Abstract: A wireless transmission method is provided in which a wireless network is constructed by a plurality of wireless transmission apparatus, a predetermined wireless transmission band is reserved and data is transmitted by radio. According to the wireless transmission method an allowable transmission error rate can be anticipated, whereby information transmission based on the unnecessary reservation of a wireless transmission band can be removed. In a wireless transmission method in which a wireless network is constructed by a plurality of wireless transmission apparatus, a predetermined wireless transmission band is reserved and data is transmitted by radio, a desired quality in a wireless transmission is selected by an arbitrary wireless transmission apparatus of a plurality of wireless transmission apparatus and a necessary wireless transmission band is reserved.

Radio access selection for multistandard terminals

Abstract: The race for higher data rates in wireless systems has produced a multiplicity of radio access methods to fulfill the quality of service needs for the next generation of mobile devices. This document presents an analysis of GERAN, UTRAN, WLAN, and Bluetooth as possible methods of accessing services via a wireless device. In light of the results, meaningful combinations for radio access methods of wireless devices are elaborated.

Increasing the throughput of multihop packet radio networks with power adjustment

Abstract: The packet radio network (PRN) is an attractive architecture to support mobile and wireless communication. Although the code assignment problem has been studied extensively on PRN, we observe that the power control problem has been ignored by most works, but may have significant impact on performance. By power control, we mean that the transmission ranges of stations are tunable. We show, given a PRN in which each host already received a code, how to adjust the powers of stations to control/improve the topology of the PRN without violating the original code assignment. Several schemes are proposed. Through simulations, we demonstrate that although the code assignment problem is NP-complete and thus computationally very expensive, using our power adjustment schemes can easily improve the network performance by about 20% with polynomial costs.

Wireless communications terminals and methods including multiple entry phonebook for multiple transceivers

Abstract: A wireless communications terminal includes a first transceiver that communicates with a first wireless communications system such as a cellular communications system. A second transceiver communicates with a second wireless communications system that typically has a shorter range than the first transceiver, such as a Bluetooth or FRS system. A multiple entry phonebook includes a first wireless communications system access number and a second wireless communications system access number for each of one or more entities. The wireless communications terminal includes a controller and/or other means that determines whether to use the first wireless communications system access number or the second wireless communications system access number in response to a request to call the corresponding entity. A wireless communication is initiated with the entity over the first wireless communications system using the first transceiver access number and the first transceiver or over the second communications system using the second transceiver access number and the second transceiver, in response to this determination.

Methods of determining a communications range of an interrogator of a wireless identification system and methods of verifying operation of a wireless identification system

Abstract: This invention provides radio frequency identification devices, wireless communication systems, communication methods, methods of forming a radio frequency identification device, methods of testing wireless communication operations, and methods of determining a communication range. According to a first aspect, a radio frequency identification device includes a substrate; communication circuitry coupled with the substrate and configured to at least one of receive wireless signals and communicate wireless signals; and indication circuitry coupled with the communication circuitry and configured to indicate operation of the radio frequency identification device. A communication method according to another aspect includes providing a radio frequency identification device including indication circuitry; receiving a wireless signal within the radio frequency identification device; and indicating operation of the radio frequency identification device using the indication circuitry after the receiving.

Dual channel redundant fixed wireless network link, and method therefore

Abstract: A dual channel redundant wireless network link formed by the Redundant Fixed Wireless Network Link device 10 of the present invention provides a very high reliable network element for mission critical wireless network application. Redundant Fixed Wireless Link device ( 10 ) with two wireless networking radio channel ( 11, 12 ) turned on simultaneously, and running networking service feature is working as Service Equipment (SE). Both wireless networking radio channel ( 11, 12 ) of the SE have the same directional wireless network coverage area. The two wireless networking radio channels ( 11, 12 ) are separated by cross polarization of antenna at same radio frequency, or different radio frequency characteristics. One Redundant Fixed Wireless Link device ( 10 ) with one of its two wireless networking radio channel ( 11, 12 ) turned on and communicating with said SE, and loaded with networking client feature is acting as Client Equipment (CE). The link quality monitor feature of the CE is monitoring the communication link between the SE and CE. When the current link quality is low or the link is down, the CE automatically switches on the alternate wireless networking radio channel ( 11, 12 ) to maintain the network communication between the SE and CE. One SE may communicate with plurality of CE in the same wireless network coverage area.

Multiantenna digital radio transmission

Abstract: Broadband wireless access theoretical limits of the spatio-temporal wireless channel digital radio design principles space-time modems based on traditional principles spatio-temporal processing using high-order statistics an experimental digital radio for MIMO advanced solutions for high mobility spatio-temporal radios for CDMA.

Cellular telephone with simultaneous radio and cellular communication

Abstract: A cellular telephone (110) forms part of a wireless communication system (100) and has simultaneous communication of radio and cellular signals. The wireless communication system (100) has a base station (115) and one or more radios (120). The cellular telephone (110) has control circuitry (205), a cellular transceiver (215), a radio transceiver (210), a microphone (220), and a speaker (225). The simultaneous communication of radio and cellular signals permits a radio user to participate in a cellular phone call and permits a cellular telephone user to participate in the radio communication. Simultaneous communication is communication of cellular and radio signals at the same time and at substantially the same time.

Integrated radio frequency interface

Abstract: An apparatus (figures 2 and 3) that may be configured to generate a wireless radio signal in response to one or more first data signals. The warless radio signal may comprise a single frequency hopping sequence configured to support one or more peripheral wireless network devices (104a-104n). The apparatus may also be configured to generate the one or more first data signals in response to the wireless radio signal.

Radio transmission system for performing multi-spot relay and radio equipment to be used therefor

Abstract: PROBLEM TO BE SOLVED: To provide a communication system and a radio communication device therefor in which communication path capacity characteristics are improved even in an unobstructed propagation environment where a transmitter and a receiver can directly view each other in a MIMO communication system. SOLUTION: The system is configured by having radio equipment 101 having a transmitter for distributing transmission data containing encoded data and training signals to a plurality of antennas and for transmitting the data from the plurality of antennas in a prescribed timing as radio signals, a plurality of pieces of radio equipment having repeaters 301a-301c for receiving the radio signals, storing them in buffers and transmitting the radio signals after delaying them for a prescribed time, and radio equipment 102 having a receiver for receiving the radio signals from the pieces of second radio equipment 301a-301c via a plurality of antennas and demodulating the coded data by using the training signals multiplexed on the received radio signals. Each of the pieces of radio equipment transmits a control signal for deciding the necessity of relay and controlling the operation of the relay. COPYRIGHT: (C)2003,JPO

Blind radio access technology discovery and monitoring for software defined radio communication systems: problems and techniques

Abstract: One of the prime goals of a reconfigurable terminal is that it shall work on a great range of systems and standards. Amongst the many features that are required to support this inter-system roaming is the ability to detect, discover or identify alternative systems. Having located alternative systems, the terminal then needs the ability to connect to them and also monitor them in order to determine how viable the level of service offered by each one is. This paper is an introductory study of the problems that a software defined radio (SDR) terminal will face during its initial power-on in a geographical area where no a priori information about the available networks is provided to the terminal.

Radio device control terminal apparatus, radio system and multimedia system constitution method

Abstract: A plurality of radio devices having a radio communication function establish a radio connection therebetween by exchanging their identifiers, and then exchange their information. Each radio device receives the identifier of another radio device as a destination via a radio device control terminal, and establishes a radio connection without requiring much time and effort of the user when connecting the radio devices. When the radio device control terminal has detected radio devices (stations) in a communicable area (where radio connection can be established) set by its radio communication function, it displays the detected radio devices as targets of radio connection establishment on its coordinate-input-enabled display section. When the user has designated the establishment of a connection between the radio devices on the display section, identifiers necessary for establishing a radio connection between the radio devices are transmitted thereto.

Radio communication system, radio communication apparatus, and radio communicating method

Abstract: A mobile station capable of connected to an information providing server via a radio link, comprises a reception history table which stores an identification of information which has been received, and a controller which prevents the same information from being received based on the identification in the reception history table.

Wireless LAN monitoring device

Abstract: A handheld mobile wireless monitoring apparatus is disclosed in which a radio receiver monitors a wireless signal across one or more wireless channels. A user interface enables a user to observe and select a predetermined parameter of the wireless signal to be evaluated. A processing circuit evaluates the wireless signal to observe the predetermined parameter. An enclosure is provided, dimensioned to be handheld by the user, for retaining the radio receiver, the processing circuit and the user interface.

Directional Radio Channel Measurements at Mobile Station in Different Radio Environments at 2.15 GHz

Abstract: We have performed extensive radio channel measurements in different radio environments at 2.15 GHz frequency. A spherical array and a wideband radio channel sounder were utilized at the mobile station in order to characterize the spatial radio channel at the mobile. The measurement setup, presented in [1], enables the full 3D spatial and polarization characterization of the wideband mobile radio channel in real-time. Based on the comprehensive dataset of over 300.000 snapshots collected along over 9 km of measurement routes we present the cross-polarization power ratio and average elevation power distribution at the mobile station in different radio environments. We also present some interesting examples showing variation of the local azimuth and elevation power distributions when the mobile moves in the urban environment. The examples demonstrate the effectiveness of the measurements in characterizing the radio propagation in difficult radio environments.