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The mine 5G is the foundation of intelligent mine construction. In order to meet the diversified application requirements of intelligent mine, it is necessary to promote the realization of mine 5G-advanced communication evolution system through 5G-advanced communication evolution technology. The current status of mine 5G technology research and system deployment is reviewed. The mine 5G has preliminarily realized audio and video call, HD video analysis, equipment remote control and other applications. However, there are some problems such as single terminal form, heavy uplink load, separate construction of 5G-advanced communication system and positioning system, etc. This paper analyzes the applicability of 5G-advanced communication evolution technology of 3GPP Release 17 in mine 5G-advanced communication. It is pointed out that RedCap lightweight terminal technology, NR direct connection communication technology and NR positioning technology will become the key technologies of mine 5G communication evolution. The key technologies of mine 5G-advanced communication evolution are studied. RedCap lightweight terminal technology can meet the research and development requirements of low-power consumption and low-cost multimode terminals of mine wireless sensors, single-channel wireless transmission mine video monitoring equipment, intelligent miner lamps and intelligent wearable devices. NR direct connection communication technology is applied to mine automatic driving vehicle-mounted terminal, roadway side equipment and emergency communication relay equipment. It can meet the requirements of low delay and high reliable transmission of mine automatic driving and emergency communication. NR positioning technology is applied to mine communication and positioning integration to meet the technical requirements of mine communication and positioning system fusion. This paper puts forward the architecture of mine 5G-advanced communication evolution system. The study provides the direction for building 5G fully connected mine, supporting multi-link wireless access and realizing the integration of communication and perception.

At present, there are more researches on the concept and development plan of intelligent mines, and less researches on the intelligent construction results and key technologies. Based on the 5-layer technical structure of intelligent mine construction, taking the intelligent construction of Daliuta Coal Mine as an example, the paper discusses the intelligent construction and effectiveness in terms of fully mechanized mining, excavation, transportation, power supply, water supply and drainage systems. A total of about 100 fixed mine positions are canceled, and more than 200 operators are reduced. The construction helps to reduce the labor costs by 40 million yuan/a, save the industrial water and electricity consumption by 30%, improve the equipment utilization by 5%, and increase the total workforce efficiency by 10%. It is pointed out that the key points of intelligent mine construction are broadening the network channel, unifying the interfaces of various subsystems, ensuring the associated equipment safe and reliable, and hiring professional personnel teams. This paper summarizes the current difficulties in the intelligent mine construction and discusses the key technologies to be tackled. The technologies include automatic coal cutting, personnel detection of mobile equipment, wireless sensing, centralized refueling, intelligent security inspection at the mine entrance and unmanned driving.

Integrated localization and wireless communication(ILWC) is a new information technology based on hardware resources and software information sharing to realize the coordination of location and communication functions. This paper briefly introduces the research progress of wireless communication technology and localization technology, and reveals that ILWC technology is the inevitable result of the bearer services expansion of wireless communication system. This study summarizes the definition and connotation of ILWC technology in different research. The core idea of ILWC is defined as 'hardware integration and software sharing'. The research progress of ILWC technology is summarized according to the two stages of equipment reuse and deep fusion. Combined with the particularity of the scene of the coal mine, the concept of ILWC in the coal mine is put forward. Based on the sharing of time, space, spectrum, computing and other resources, the technology is the fusion technology of communication function and localization function with an automatic scene perception and dynamic and adaptive resource allocation mechanism. The adaptability of underground ILWC in roadway, central substation, underground parking lot, coal working face and other scenes is discussed. It is pointed out that the challenges faced by underground ILWC are the complexity of underground wireless channel, unbalanced deployment of base stations and precise recognition of complex underground scene.

The mine wireless communication system has the advantages of wide communication coverage, convenient connection, good mobility, easy to establish, simple setup and maintenance, etc. It plays an irreplaceable role in in the construction of mine intelligence. The whole mine wireless communication system mainly include WiFi(IEEE 802.11b/g/n/ac), 3G, 4G, 5G and WiFi6(IEEE 802.11ax) system. 3G system is gradually replaced. 4G and WiFi system are gradually reduced. 5G and WiFi6 system are at the initial stage, and will gradually become the mainstream. The 4G, 5G and WiFi/WiFi6 systems are analyzed from the aspects of technical points, main functions and applications. And the advantages and disadvantages of each system are pointed out in this paper. ① The main disadvantage of the mine 4G wireless communication system is that the bandwidth and real-time indicators cannot meet the needs of application scenarios such as high-definition intelligent video and remote control. ② The problems of 5G in practical use are listed as following points. In the case of multiple systems and multiple antennas, there is a security problem of wireless transmission signals. 5G base stations are mainly explosion-proof and intrinsically safe types, which are large in quality and volume. There are problems of inconvenient to use and limited in use. 5G terminal ecology is lacked. The communication modules are expensive and power consumption is high. It does not have the conditions for large-scale industrial applications. There are few practical application cases, and the application scenarios need to be further explored. ③ WiFi6 wireless communication system has high latency, relatively low mobility and reliability. The mobile phone terminal is not mature enough, which affects the quality of voice calls. Based on the above analysis, it is pointed out that the demand of intelligent mine for wireless communication system is the demand of large bandwidth, low latency, high reliability, multi-access, multi-system, multi-interface, and position information. Finally, this study points out the development trend of mine wireless communication system. The trend includes system fusion (wireless communication and wired communication fusion, wireless communication internal fusion, wireless communication system and other system fusion). It also includes communication and positioning integration, equipment intrinsic safety, terminal module low power consumption and protocol interface standardization.

In order to solve the problems of various types, complex system and low resource sharing rate of software and hardware equipment, difficult network upgrading and transformation, and the incapability to meet the requirements of vertical services due to limited uplink and downlink transmission bandwidth and long total service delay, this paper proposes to introduce multi-access edge computing(MEC) technology into mine network to provide support for the realization of intelligent mine. For the intelligent mine service types of video monitoring, delay sensitive and connection, the application mode of MEC is discussed, and the characteristics of MEC supporting multiple protocols and equipment access are analyzed. It is pointed out that MEC is the only choice to provide integrated management and control based on the existing underground multiple protocols and equipment, and is the best solution to provide undifferentiated high-quality end-to-end service for users. The intelligent mine network computing tree model based on business requirements is established, and its evolution is divided into three stages, namely Pre-5G, 5G and Beyond-5G(6G). The main characteristics and symbolic technologies of each stage are analyzed, as well as the business characteristics such as load balance, business mobility, data security, scalability and integration characteristics. It is pointed out that each characteristic is the worst in the first stage and the best in the third stage. However, there is still a gap to achieve the goal of truly universal hardware devices and fully standardized interfaces. Combined with the computing tree model, the intelligent mine network MEC deployment model is proposed. It is pointed out that the model is based on a three-level flat structure with depth of 2, which can give full play to the edge computing capability of nodes at all levels, and dynamically select task unloading strategy while taking into account the load balance of nodes, so as to complete efficient task coordination. Moreover, the functions of nodes can be selected and flexibly deployed according to the actual situation on the ground or underground, which is suitable for all stages of intelligent mine construction.

The 5G application scenarios such as remote control, high-definition video, unmanned mine car and unmanned aerial vehicle in intelligent mine put forward new requirements for the uplink rate of wireless network. However, the current 5G network uplink rate is insufficient, which leads to the limitation of intelligent mine business. And the existing 5G network uplink rate enhancement algorithm has limited range to improve the uplink rate. In order to solve the above problems, this paper proposes an uplink rate enhancement algorithm for 5G network in intelligent mine. By using supplementary upload technology, the spectrum resource aggregation is realized by overlaying Sub-3 GHz low band on the high band of C-Band, and the uplink rate of the network is improved by frequency domain resource allocation and time domain resource scheduling. In the middle-near point area, when the base station performs uplink data scheduling, the user equipment uses the 3.5 GHz frequency band to send uplink data in the uplink time slot of the C-Band frequency band, and uses the 1.8/2.1 GHz frequency band to send uplink data in the downlink time slot of the C-Band frequency band. In the far point area, the 3.5 GHz frequency band uplink is limited, and the user equipment only uses the 1.8/2.1 GHz frequency band to send uplink data. The test results show that the algorithm improves the mine near-point area, middle-point area and far-point area uplink rate by 17%, 41% and 213% respectively, and the average network uplink rate is significantly improved.