摘要:
Described is a technology by which a remote or local geo-location service provides white space information that one or more client devices and/or base stations may use to determine which white spaces are available for use, e.g., for wireless networking. Because of the information, low-threshold sensing is not needed by the client devices and/or base stations to know which white spaces are available. The service computes the available white spaces for a given location based upon television transmitter parameters, elevation data, and information received regarding any operational wireless microphones.
摘要:
Functionality is described by selecting a channel in an environment in which non-privileged entities have subordinate access rights to spectrum compared to privileged entities. The functionality operates by identifying spectrum that is available to all nodes involved in communication (where the nodes are associated with non-privileged entities). The functionality then generates a suitability assessment for each candidate channel within the available spectrum. The functionality selects a channel having the most desirable suitability assessment. The functionality can form a suitability assessment for a candidate channel of arbitrary width, e.g., by combining suitability assessments associated with constituent spectrum units within the candidate channel.
摘要:
A new media access control (MAC) protocol for cognitive wireless networks is described. The new MAC protocol allows each of multiple nodes, such as cell phones and computers with wireless, to determine utilization of a communication spectrum, such as the television broadcast band. The nodes collaborate to achieve a combined view of spectrum utilization in their local vicinity, in which scheduled users and empty time segments are mapped across a wide range of frequencies. Nodes negotiate with each other to reserve idle segments of the spectrum for packet exchange on negotiated frequencies. Control packet structure allows nodes to become prescient of the local spectrum utilization during handshaking. A cognitive device operating under the new MAC has a first radio that both scans the spectrum and monitors a control channel; and a second reconfigurable radio with adjustable parameters, including frequency and bandwidth, for packet transmission.
摘要:
The coexistence of a plurality of different wireless networks that concurrently operate in a common geographic region is optimized. A query is received from a wireless node requesting advice on specific portions of a radio frequency spectrum to use. A spectrum recommendation procedure is then run to generate advice on recommended portions of the radio frequency spectrum for the wireless node to use in order to minimize one or more of interference in the spectrum, or noise in the spectrum, or contention in the spectrum. A recommendation reply is then sent to the wireless node which includes information specifying the recommended portions of the radio frequency spectrum for the wireless node to use in order to minimize one or more of interference in the spectrum, or noise in the spectrum, or contention in the spectrum.
摘要:
Embodiments include processes, systems, and devices that allow a white space base station to request available frequency ranges for white space transmission in a local area. A white space finder service models a primary user device's transmission signal propagation area using terrain data associated with the local area of the primary user device. The white space finder service also determines, based on the location of the white space base station and the modeled propagation area, one or more locally available, non-interfering frequency ranges and provides them to the white space base station. The white space base station compares the provided frequency ranges to policies and selects one or more of the available frequencies that accommodate the policies. The white space base station also maps the transmission frequency ranges to virtual frequency ranges for transmission by a software-defined radio employing spectrum virtualization.
摘要:
Described is incorporating white space networking components into a network stack. A user mode spectrum access control component determines which white space channels are currently allowed for use based upon policy, current operating status and availability information obtained from one or more sources. A white space service (e.g., in the WLAN service) receives the availability information. The white space service includes a discovery module that discovers other nodes, and a channel migration module that changes from the current channel to another channel if the current channel is no longer allowed for use. A kernel mode (NDIS layer) white space driver through a miniport driver controls the channel in use as the current channel. An automatic configuration module is provided that switches to Wi-Fi network communication when a Wi-Fi network is present, and switches back when a Wi-Fi network is not present.
摘要:
Dynamic time-spectrum block allocation for cognitive radio networks is described. In one implementation, without need for a central controller, peer wireless nodes collaboratively sense local utilization of a communication spectrum and collaboratively share white spaces for communication links between the nodes. Sharing local views of the spectrum utilization with each other allows the nodes to dynamically allocate non-overlapping time-frequency blocks to the communication links between the nodes for efficiently utilizing the white spaces. The blocks are sized to optimally pack the available white spaces. The nodes regularly readjust the bandwidth and other parameters of all reserved blocks in response to demand, so that packing of the blocks in available white spaces maintains a fair distribution of the overall bandwidth of the white spaces among active communication links, minimizes finishing time of all communications, reduces contention overhead among the nodes contending for the white spaces, and maintains non-overlapping blocks.
摘要:
Functionality is described for discovering a channel within an environment in which non-privileged entities have subordinate access rights to spectrum compared to privileged entities. The functionality operates by investigating spectrum units within the spectrum for the presence of the channel. In one case, the functionality operates by investigating the spectrum units in linear succession; in another case, the functionality advances in a staggered fashion over the available spectrum. Functionality is also described for handling disconnection by a node from a channel. The functionality allows the node to convey its disconnection status to other communication participants. In one case, various aspects of the functionality are implemented by performing analysis in the time domain.
摘要:
Dynamic time-spectrum block allocation for cognitive radio networks is described. In one implementation, without need for a central controller, peer wireless nodes collaboratively sense local utilization of a communication spectrum and collaboratively share white spaces for communication links between the nodes. Sharing local views of the spectrum utilization with each other allows the nodes to dynamically allocate non-overlapping time-frequency blocks to the communication links between the nodes for efficiently utilizing the white spaces. The blocks are sized to optimally pack the available white spaces. The nodes regularly readjust the bandwidth and other parameters of all reserved blocks in response to demand, so that packing of the blocks in available white spaces maintains a fair distribution of the overall bandwidth of the white spaces among active communication links, minimizes finishing time of all communications, reduces contention overhead among the nodes contending for the white spaces, and maintains non-overlapping blocks.
摘要:
Architecture that enables wireless narrowband devices (e.g., wireless microphones) and white space devices to efficiently coexist on the same telecommunications channels, while not interfering with the usability of the wireless narrowband device. The architecture provides interference detection, strobe generation and detection and, power ramping and suppression (interference-free coexistence with spectrum efficiency). The architecture provides the ability of the white space device to learn about the presence of the microphone. This can be accomplished i using a geolocation database, reactively via a strober device, and/or proactively via the strober device. The strober device can be positioned close to the microphone receiver and signals the presence of a microphone to white space devices on demand. The strober device takes into consideration the microphone's characteristics as well as the relative signal strength from the microphone transmitter versus the white space device, in order to enable maximum use of the available white space spectrum.