We propose such a framework to ensure that secondary users can transmit over the same spectrum band as the primary user at the same time at a higher power without disturbing the communications of the primary network.
Assume that a subset of SUs, denoted by Sub, are allowed to transmit over the same spectrum band as the PT in each time slot, as long as their transmissions do not disturb the normal communications of the primary network.
This is especially useful in cognitive radio scenarios, in which high spectral containment and resolution permit secondary users to exploit appearing and vanishing spectral time-frequency holes in the communications of the primary system.
Figure 10 Impact of peak interference power Q pk on the outage probability P out of point-to-multipoint communications in which the number of primary users and secondary users are set to N = M = 5 ( k denotes the number of secondary users that cannot receive the common packets successfully).
It espoused a program of large-scale government ownership of primary industries, banking, transportation and communications, and even agricultural land.
As the output of primary produce increased, it became necessary to extend and improve communications.
The long-axis diameter of primary duct was measured using the electronic caliper provided by the picture archiving and communications system (Angora PACS, Datamed Medical Systems, Ankara, Turkey).
Surgeries by excision of primary and metastatic tumors directly stop the releasing of CTCs and cut off the bilateral communications between CTCs and tumor masses.
Lower-intensity interventions involving 5 minutes or less of primary care provider counseling supplemented by patient self-help materials, telephone counseling or interactive health communications.
With the purposes of improving outage performance of the primary system and realizing communications of the secondary users without a direct link, we propose a spectrum sharing protocol where a relay assists the communications of the primary and secondary users, as depicted in Figure 1. Figure 1 Cognitive relay network model.
