摘要:
A method and apparatus for allocation of shared spectrum in a wireless communication system uses a radio frequency (RF) beacon signal that is transmitted between access points of the wireless communication system. The information content of the RF beacon signal includes an identifier of the access point that generated the signal, identifiers of clients of that access point; and identifiers of the communication channels assigned to those clients. The client identifier may include at least part of an Internet Protocol (IP) address of the client. Additionally the beacon signal may contain client attributes to enable negotiation of the sharing of available communication channels between access points and clients.
摘要:
During operation of a secondary communication system, cells (106) are formed by a plurality of localized nodes (104) to alert other nodes within the cell of frequencies which must be protected or otherwise avoided. All nodes within the cell monitor a differing subset of all frequencies available, and share information with respect to acceptable and protected frequencies with each other via low-power, short-range communication. Each node then forms a list of available channels for communication, and chooses a single node to report this information back to controller.
摘要:
The presence of the non-television transmission within a channel is used to indicate that secondary non-licensed usage of the channel is permitted. Specifically, if secondary users incorporate the means to identify the unique modulation signature of the secondary user, decoding of a beacon signal may not be necessary. With the above in mind, a radio will be prevented from transmitting within a frequency band when no transmission within the licensed spectrum is currently taking place; the licensee is currently transmitting on the spectrum (e.g., television transmissions are taking place utilizing the spectrum, or the radio cannot sense the presence of a data channel (beacon).
摘要:
A communications system and method for exchanging spectrum usage information through a drop box (100) includes one or more central stations (101) that defines a region of operation. A central drop box (102) is associated with the central station (101) for providing a database of spectrum usage information. Stations (103, 105, 107) using the communications system may submit information regarding spectrum usage to the central drop box (102) that affects the region of operation (109, 115) for providing the most efficient and non-interfering uses of the frequency spectrum.
摘要:
During operation of a secondary communication system, cells (106) are formed by a plurality of localized nodes (104) to alert other nodes within the cell of frequencies which must be protected or otherwise avoided. All nodes within the cell monitor a differing subset of all frequencies available, and share information with respect to acceptable and protected frequencies with each other via low-power, short-range communication. Each node then forms a list of available channels for communication, and chooses a single node to report this information back to controller.
摘要:
A communications system and method for exchanging spectrum usage information through a drop box (100) includes one or more central stations (101) that defines a region of operation. A central drop box (102) is associated with the central station (101) for providing a database of spectrum usage information. Stations (103, 105, 107) using the communications system may submit information regarding spectrum usage to the central drop box (102) that affects the region of operation (109, 115) for providing the most efficient and non-interfering uses of the frequency spectrum.
摘要:
The radio frequency (RF) environment is scanned and analyzed prior to entering a building or otherwise non-ideal propagation path environment. Upon entering the building or non-ideal propagation path environment, the mobile unit will scan the RF environment from within the building. An attenuation factor is determined for various frequencies. A channel then chosen to operate on in the cognitive system based on the attenuations of the various frequencies.
摘要:
The radio frequency (RF) environment is scanned and analyzed prior to entering a building or otherwise non-ideal propagation path environment. Upon entering the building or non-ideal propagation path environment, the mobile unit will scan the RF environment from within the building. An attenuation factor is determined for various frequencies. A channel then chosen to operate on in the cognitive system based on the attenuations of the various frequencies.
摘要:
A node of a wireless mesh network assigns a radio frequency (RF) channel for operation by sensing an interference level in a number of RF channels, determining which RF channels are available for use and selecting the available RF channel having the best performance. The node then attempts to communicate with neighboring nodes of the wireless mesh network using the selected RF channel. If communication with a sufficient number of nodes is not achieved, the node selects an available RF channel having the next best performance, and attempts to communicate with neighboring nodes using the selected RF channel. The process is repeated until the node can communicate with a sufficient number of nodes. The selected RF channel is then assigned for node operation.
摘要:
A cognitive radio (CR) device (208 and/or 218) avoids interference with an incumbent (207) receiver by determining maximum allowed transmit power levels of the CR device based on estimates of the incumbent signal level and transmit splatter levels of the CR device. The CR device (208 and/or 218) avoids interference with the incumbent receiver while transmitting with maximum transmit power levels.