We propose an uplink full-duplex (FD) cooperative non-orthogonal multiple access (NOMA) system, where a dedicated Full-duplex (FD) relay is used to help two uplink users transmitting information to the base station. A novel FD relay transmission mode is proposed, in which the FD relay utilizes successive interference cancellation (SIC) and self-interference cancellation to decode two users symbols at the relay receiving antenna, and the relay transmitting antenna transmits superimposed signal to the base station using superposition coding. In this paper, we also consider a more realistic scenario where selfinterference cancellation is imperfect. Hence, the residual-self interference exists. Moreover, the ergodic sum rate and the outage probability of the proposed system are investigated and the accurate analytical expressions are derived. Simulation results validate that, compared with the uplink half-duplex (HD) cooperative NOMA system and the uplink HD cooperative orthogonal multiple access (OMA) system, our proposed system obtains better performance of the ergodic sum rate and outage probability in the main signal to noise ratio (SNR) regime.

In this paper, a 60 GHz complementary metal-oxide-semiconductor (CMOS) balun low-noise amplifier (LNA) was implemented for millimeter-wave communication. To improve the gain and noise performance, slow-wave coplanar waveguides (S-CPW) with high quality factor were designed as input, output, and inter-stage matching networks. At the input port, a balun transformer provides additional passive gain while performing the singled-ended to differential conversion. Implemented in a 28-nm CMOS process, simulated results show that the proposed LNA exhibits a simulated linear gain of 16 dB and a noise figure of 5.6 dB at 60 GHz, with a 3-dB gain bandwidth of 5 GHz (58 GHz–63 GHz). The input return loss is better than −25 dB at the central frequency. The simulated input third-order intercept point (IIP3) is −5 dBm. The circuit draws 35 mA from 1 V supply voltage.

In this paper, we analyze the effective capacity gains of opportunistic spectrum-sharing with imperfect channel information. We consider that a secondary user may access the spectrum allocated to a primary user as long as the average interference power, inflicted at the primary's receiver as an effect of the transmission of the secondary user, remains below predefined power limits. We consider partial channel information of the link between the secondary user transmitter and primary user receiver is available to the secondary user. We derive the optimal power allocation strategy to achieve the maximum effective capacity under Rayleigh fading with imperfect channel information. Finally, we also obtained expressions for the average expenditure-power required to achieve the effective capacity with channel estimation error variance. Numerical results are conducted to corroborate our theoretical results.

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