Uplink Radio Resource Allocation in AF and DF Relay-Assisted Networks With Limited Rate Feedback

Abstract

In this paper, we develop quantized ergodic resource allocation in uplink OFDMA-based relay assisted networks in which both Amplify and Forward (AF) and Decode and Forward (DF) protocols are investigated. The main objective is to maximize the average sum rate subject to the power constraint at the users and relays. Using dual decomposition technique and block coordinate descent algorithm (BCDA), we then obtain near-optimal solution for the proposed problems. The proposed methods significantly decrease the required feedback information which reduce the overhead on the bandwidth as well as cost. Furthermore, we investigate the impact of noisy feedback channel on the system performance. Extensive simulation results also presented which indicate that DF outperform AF in various conditions. It is also observed that by increasing the number of quantization regions, the average sum rate approaches to the case in which full channel state information is available.Index Terms-Amplify-and-Forward relaying, Decode-andForward relaying, dual decomposition, Orthogonal Frequency Division Multiple Access, limited rate feedback.

Pricing user scheduling and precoding in relay‐assisted massive MIMO systems

“…In the proposed model, the 5 relays locate on the circle with the radius of 7, and each relay is equipped with antennas. The near users are randomly deployed in the ring with radius of [5, 10]. Following the cell radius of [24, 25], the far users are randomly deployed at cell edge, and the distance between the relay and far users obey the uniform distribution of [8, 13].…”

“…The reliable and efficient communication in harsh environments still is a tricky problem, such as the communication in mountainous zones, or at cell‐edge, which is difficult to be solved even with more transmitting antennas at BS. Thus, some researchers utilise the relay for enhancing the communication quality [4–7]. In [4, 5], the authors consider the data transmission of the far users with the help of relays, while the authors consider the uplink channel.…”

“…Thus, some researchers utilise the relay for enhancing the communication quality [4–7]. In [4, 5], the authors consider the data transmission of the far users with the help of relays, while the authors consider the uplink channel. The uplink relay‐assisted model cannot be well applied to the user scheduling in the downlink channel.…”

Limited Feedback Scheme for Device-to-Device Communications in 5G Cellular Networks with Reliability and Cellular Secrecy Outage Constraints

“…Note that, designing limited rate feedback systems with incorporating feedback error is complicated, especially for our scheme with two interfering links. In this paper, to consider the feedback error, we utilize the scheme which is commonly used in the literature [30], [45]- [48]. We consider the memoryless feedback channel which characterized by index transition probabilities ρ C m,m ′ (m, m ′ = 0, · · · , M − 1) for cellular link which is the probability of receiving index m in BS given the index m ′ was sent by CU, and ρ C n,n ′ (n, n ′ = 0, · · · , N − 1) for D2D pair which is the probability of receiving index n in TD2D given the index n ′ was sent by RD2D.…”

Resource allocation for full‐duplex–based heterogeneous cellular networks considering back‐haul capacity

“…CHD-3 imposes the maximum capacity of wireless back-haul links, where it is denoted by C max BH . The data rate of DF relays is the minimum of its input and output rate; it is shown in the literature [21][22][23][24] that instead of minimization, we can apply CHD-4. Moreover, the OFDMA assumption is enforced by constraints CHD-5 and CHD-6 for the first and second time slots, respectively.…”