List of Articles Power allocation

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  1 - An OFDM-DCSK based Approach for D2D Emergency Communications
  Majid Mobini
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• Open Access Article
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  2 - Optimal Power Allocation for CR Networks with Direct and AF Relay-Aided Transmissions
  anahita Pakdelian Rouhollah Aghajani
  One of the most prominent challenges in meeting the demand is the scarcity of radio resources. Cognitive radio is one of the techniques has been proposed for efficiently utilizing the radio resources. In Cognitive Radio CR) networks, the CR users have opportunities to a More

  One of the most prominent challenges in meeting the demand is the scarcity of radio resources. Cognitive radio is one of the techniques has been proposed for efficiently utilizing the radio resources. In Cognitive Radio CR) networks, the CR users have opportunities to access the licensed spectrum bands assigned to the primary users (PUs). Since the PUs have priorities to use the bands, the CR users are not allowed to generate unacceptable interference to them. In this paper, we investigate power allocation schemes for CR networks with two users where one users uses direct transmission and the other uses AF relay-aided transmissions. We first formulate an overall rate optimization problem with interference constraints to the PU and peak power constraints at each node and obtain solutions by theoretical analysis. We also simulate the solution base on different location of the relay and different location of the PU network.we compare the results with equal power allocation Manuscript profile
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  3 - Power Allocation for Cognitive Relay System over Rayleigh Fading Channels
  Rouhollah Aghajani Reza Saadat Mohammad Reza Aref
  In this paper we consider two networks, a primary network and a secondary cooperative communication network. In the secondary network, a source is assisted by cognitive relay nodes which allow it to coexist with the primary network. The secondary users must work under t More

  In this paper we consider two networks, a primary network and a secondary cooperative communication network. In the secondary network, a source is assisted by cognitive relay nodes which allow it to coexist with the primary network. The secondary users must work under the noise floor of the primary network to achieve low interference for the primary network. Simultaneously, the secondary users should be able to complete their duty. Therefore, the cooperative system utilizes the incremental and selective decode-and-forward (ISDF) relaying protocols. In ISDF protocol, the relay sends signal in necessary situations. Thus, the ISDF cooperative scheme is considered for the secondary network in order to reduce the interference to the primary users. Under some constraints on the transmitting power from the source and relay nodes in the secondary network, they can operate below the noise level of the primary network. Under these constraints, we minimize the symbol error rate of the secondary network. It is seen that in the ISDF protocol the interference produced with the relay to the primary users is very low. Manuscript profile