Abstract:
During operation of a secondary communication system, nodes having different channel monitoring capabilities or requirements will cooperatively monitor possible frequencies for transmissions, each node using only a subset of all possible modulation sensing schemes. All nodes will share channel occupancy information to other nodes within the communication system. For example, a first group of nodes may monitor possible frequencies for television transmissions, while a second group of nodes may monitor the possible frequencies for APCO 25 transmissions. A group of nodes may also cooperatively monitor possible frequencies for more than one type of modulation transmission. Channel information will be shared among the nodes.
Abstract:
A wireless receiver receives (101) a desired wireless signal and then detects (102) self-sourced intermodulation products other than with respect to the desired wireless signal to provide corresponding detected results. The wireless receiver then uses (103) these detected results to control gain as corresponds to the desired wireless signal.
Abstract:
A method and apparatus for allowing communication units (100) to utilize non-licensed spectrum is provided herein. In particular, when a radio (100) determines a need to transmit within non-licensed spectrum, the radio (100) searches for a beacon being transmitted (303). The beacon identifies a priority of the current user of the non-licensed spectrum (305). If the radio's (100) priority is higher than the current user of the non-licensed spectrum, or if no beacon is heard, the radio (100) may begin transmitting within the non-licensed spectrum (311). As part of the radio's (100) transmission, a beacon will be broadcast by the radio (100) identifying the radio's (100) priority.
Abstract:
In a cognitive radio, a method of establishing an operational policy for use in a Peer-to-Peer (P2P) group, wherein the policy can be described by layers of policy parameters with progressively higher layers having a progressively increasing number of parameters, involves determining that a policy change is to be made from a current policy (316); requesting policy information from at least one P2P group member (320); receiving a policy description from the at least one P2P group member (322); and implementing a change in the lowest layer policy parameter to establish a new operational policy (324).
Abstract:
In certain embodiments of a cognitive radio (100), a method of establishing operational policies, involves determining that a new policy decision should be made; requesting a policy decision from an authority having more computing power than the cognitive radio; receiving the policy decision from the authority; and implementing the policy decision in the cognitive radio. Other embodiments may incorporate more, fewer or other elements.
Abstract:
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.
Abstract:
There is disclosed a circuit (60) responsive to control signals applied thereto for alternatively sourcing and sinking current at an output which includes a first controlled current source (48) responsive to selective ones of the control signals for sourcing a current of a predetermined magnitude to the output of the circuit; a second controlled current source (50) responsive to other selective ones of the control signals for sinking a current of a predetermined magnitude from the output of the circuit; and a disabling circuit (42, 44) for respectively disabling said first and second controlled current sources whenever the voltage potential at the output of the circuit becomes greater or less than a predetermined value respectively.
Abstract:
BROADCAST SIGNAL DETECTED INDICATION SYSTEM In a radio having an in phase multiplier (A) for providing an in phase detected signal, a detection unit for receiving this signal and for determining whether this signal includes any negative polarity components which would indicate that a viable broadcast signal does not exist on the incoming frequency of interest. This detection unit can include a comparator (11) for comparing the incoming signal against a selected reference value. The invention can also include a signal quality evaluation unit (58) for providing either a digital or analog quality signal that can also effect the output and be used by appropriate processing circuitry to further refine the channel selection process.