In this paper, a grouping-based uplink orthogonal frequency division multiple access (OFDMA) random access method is studied which can improve users’ satisfaction in the next generation wireless local area networks (WLANs). The next generation WLANs standard, IEEE 802.11ax introduces a random access mechanism, uplink OFDMA random access (UORA), to allow users to access channel randomly. Although UORA has the advantages of low signaling overhead, no need to report uplink transmission requirements, it does not have any characteristics to improve users’ satisfaction. Because the AP can’t allocate resources to users adopting UORA, some users’ quality of experience (QoE) will decline greatly. In this paper, a grouping-based UORA (G-UORA) method is proposed. The AP determines the number of groups, and then clusters users to different groups according to their utility. Then, the AP assigns resources to these groups to maximize the total utility of all users. We present a theoretical utility prediction model of G-UORA and propose the corresponding resource allocation algorithm based on utility. According to simulation results, the algorithm achieves better users’ satisfaction and fairness than the traditional UORA mechanism in IEEE 802.11ax and the user utility gain is 1.6 times. Therefore, the proposed method has greater practical significance.

本文研究了一种基于分组的上行正交频分多址（OFDMA）随机接入方法，该方法可以提高下一代无线局域网（WLAN）中的用户满意度。下一代WLAN标准IEEE 802.11ax引入了随机访问机制，即上行OFDMA随机访问（UORA），以允许用户随机访问信道。尽管UORA具有低信令开销的优点，但无需报告上行传输要求，但它没有任何特性可以提高用户的满意度。由于AP无法将资源分配给采用UORA的用户，因此某些用户的体验质量（QoE）将大大下降。本文提出了一种基于分组的UORA（G-UORA）方法。AP确定组数，然后根据用户的效用将用户分为不同的组。然后，AP将资源分配给这些组以最大化所有用户的总效用。我们提出了一种理论的G-UORA效用预测模型，并提出了基于效用的相应资源分配算法。根据仿真结果，该算法比IEEE 802.11ax中的传统UORA机制具有更好的用户满意度和公平性，用户效用增益为1.6倍。因此，该方法具有较大的现实意义。该算法比IEEE 802.11ax中的传统UORA机制具有更好的用户满意度和公平性，用户效用增益为1.6倍。因此，该方法具有较大的现实意义。该算法比IEEE 802.11ax中的传统UORA机制具有更好的用户满意度和公平性，用户效用增益为1.6倍。因此，该方法具有较大的现实意义。