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In order to meet the ever-increasing traffic demands, the combination of fiber and Millimeter Wave (mmWave) is expected to play a key role for 5G Centralized-Radio Access Networks (C-RANs). Due to the inefficiency of the Common Public Radio Interface for the Baseband Unit (BBU)-Remote Radio Head (RRH) communication, analog-Radio-over-Fiber (a-RoF) technology is considered a promising solution, mainly due to the RRH simplification and lower fronthaul requirements it imposes. In such mmWave a-RoF C-RANs, efficient Medium Transparent-Medium Access Control (MT-MAC) protocols are needed able to meet the challenging 5G requirements. To this end, in this paper, we propose a gated service MT-MAC protocol which authorizes each user to transmit the amount of data it requested. A detailed delay model is proposed, which is validated through simulations for different fiber lengths, network load conditions and number of available optical wavelengths. Moreover, the proposed protocol is compared with the state-of-the-art (SoA) and is shown to achieve up to 20 times higher throughput, 2 times lower delay with 100% lower blocking probability and 5 times higher data wavelength utilization, while being able to adapt to varying network traffic conditions. Our proposal also attains sub-ms latency in most cases, constituting it a promising candidate for next generation mmWave a-RoF C-RANs.
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... The main hurdle with these algorithms is that the resource allotment to the users is fixed irrespective of their current requirements leading to a higher delay. This issue has been resolved in mobile interleaved polling (MIP) [27] and gated MT-MAC (gMT-MAC) [28] algorithms, which improved the performance of the network. However, the MIP algorithm [27] have not considered the delay in registration and identification of the users in the overall delay of the RoF network. ...
... However, the MIP algorithm [27] have not considered the delay in registration and identification of the users in the overall delay of the RoF network. Further, in gMT-MAC [28], the user registration and identification delay is not optimized for a high user density RoF network, which degrades the network performance. ...
... However, these approaches consider the fixed polling scheme for the data transfer phase and do not consider the user traffic demands, which degrades the network performance. Further, gMT-MAC [28] considers a random-access approach to register and identify all the users present in the cells of the RAUs and uses a gated polling approach for data transfer. In this approach, the users that remain in the same RAU's cell in the following resource allocation cycle also have to contend with the newly arrived users in the cell for re-identification. ...
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... Further, we compare the proposed algorithms with the state-of-the-art algorithms, like MIP [21], MT-MAC [18], and gMT-MAC [29] for Poisson traffic, as shown in Fig. 10a. The performance of the single-gate polling for single wavelength architecture is similar to the MIP algorithm. ...
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