Network entry and device discovery for cognitive radio networks

A method comprising:

• scanning (330) a plurality of channels for a beacon of a target device for a scan duration, and
• if (335) the beacon of the target device is not detected:
• randomly selecting (345) an advertise duration from among a set of predefined durations,
• transmitting (350) an advertising beacon on a select channel (340) during the advertise duration, and
• if (355) a response to the advertising beacon is not received from the target device:
• repeating (365) the scanning (330) of one or more of the plurality of channels and transmitting (350) of the advertising beacon at another select channel;
• otherwise:
• establishing communication (375) with the target device.

A method of network discovery by a device (400) among a plurality of channels having primary (490) and secondary (400) users, comprising:

• if (115) the device is paired with a target device:
• if (315) the device is not a master of a master-slave pair:
• scanning (330) a plurality of channels for a beacon of the target device for a scan duration, and
• if (335) the beacon of the target device is not detected:
• transmitting (350) an advertising beacon on a select channel (340) during an advertise duration (345-360), and
• if (355) a response to the advertising beacon is not received from the target device, repeating (365) the scanning (330) of one or more of the plurality of channels and transmitting (350) of the advertising beacon at another select channel (340);
• otherwise, if (315) the device is the master of the master-slave pair, transmitting (390) an advertising beacon on a select channel (385);
• and
• establishing (145) communication with the target device;
• otherwise, if (115) the device is not paired with the target device:
• selecting (215) a channel of the plurality of available channels;
• monitoring (220) the channel to determine a classification of the channel based at least upon whether a primary or secondary user is detected (230, 240),
• storing (440) the classification of the channel, and
• repeating (270) the selecting (215) and monitoring (220) until each of the plurality of available channels has been classified;
• and
• selecting (125) a select channel from among one or more of the plurality of channels at which at least one secondary user is detected, and
• establishing communication (125) with the at least one secondary user on the select channel.

An apparatus (400) comprising:

• a receiver (410);
• a transmitter (430);
• a controller (450) that is configured to control the receiver to tune to each channel of a plurality of channels;
• a channel classifier (420) that is configured to determine a classification of each channel as being one of:
• used by a primary user (240),
• used by one or more secondary users (230),
• used by an unknown class of user (260), and
• unused (255);
• and
• a memory (440) that is configured to store the classification of each channel,
• wherein the controller (450) is configured to control the transmitter (430) to selectively effect each of (125):
• joining a network on a select channel that is classified as being used by one or more secondary users, and
• establishing a network on a select channel that is classified as being unused.

An apparatus (400) comprising:

• a receiver (410),
• a transmitter (430), and
• a controller (450) that is configured to:
• control the receiver (410) to scan (330) each of a plurality of channels for a beacon of a target device for a scan duration, and
• if (335) the beacon of the target device is not detected:
• randomly select (345) an advertise duration from among a set of predefined durations, and
• control the transmitter (430) to transmit (350) an advertising beacon on a select channel (340) during the advertise duration (345-360), and
• if (355) a response to the advertising beacon is not received from the target device, repeating (365) the control of the receiver (410) to scan (330) one or more of the plurality of channels and the control of the transmitter (430) to transmit (350) the advertising beacon at another select channel (340);
• otherwise, if (335, 355) the target device is detected, control the transmitter (430) and receiver (410) to establish communication (375) with the target device.