我們在有多個次要基地台(secondary base stations)之合作式感知無線電網路(cooperative cognitive radio networks)上考慮在傳輸中斷(outage probability constraints)下之協調之波束設計問題(coordinated beamforming design problem)，並且次要基地台配備使用分時多工存取(time devision multiple access)之全雙工(full-duplex)傳收機。所有次要基地台只知道局部通道分佈資訊(local channel distribution information)。一系列的近似方法被用來解決這個問題，像是半正定放寬(semidefinite relaxation)和第一皆近似(first-order approximation)方法。藉由解一連串凸近似問題(convex approximation problem)我們得到了一個接近最佳的解，也就是，提出來的連續凸近似(successive convex approximation)演算法產生了一個令人滿意的解。我們分析證明了{\bf P1}之解之任意一個極限點是一個平穩點(stationary point)。針對半雙工(half-duplex)傳收機制定協調之波束設計問題，並且在模擬裡存在一個全雙工與半雙工之折衷。此外，我們可以觀察到自干擾(self-interference)限制了全雙工傳收機的表現。藉由比較連續凸近似演算法與天線選擇(antenna selection)、最大比例傳送(maximum ratio transmission)之表現來檢驗其演算法之表現。

We consider the coordinated beamforming design problem for the cooperative cognitive radio networks (CCRN) with multiple secondary base station (SBS) under outage probability constraints, and the SBSs are equipped with full-duplex (FD) transceivers applying time division multiple access (TDMA) for transmission. All SBSs only know the local channel distribution information (CDI). A series of approximation methods are employed to deal with this problem, such as semidefinite relaxation (SDR) and first-order approximation method. We obtain the near-optimal solution via solving a sequence of convex approximation problems, i.e., the proposed efficient successive convex approximation (SCA) algorithm yields a satisfactory solution. We analytically prove that any limit point of the conservative approximation problem P1’s solution is a stationary point. The coordinated beamforming design problem for the SBS with half-duplex (HD) transceiver is formulated, and there exists a tradeoff between FD and HD transceivers in the simulation results. Furthermore, we can observe that the self-interference limits the performance of FD transceivers. The performance of the proposed SCA algorithm is examined
by comparing with exhaustive search method, antenna selection (AS) scheme, and maximum ratio transmission (MRT).

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