I. Introduction
In the current era of rapid technological development, intelligent management has become the key for many places to improve operational efficiency and security. As an important part of personnel access control, visitor management is also undergoing a profound transformation from the traditional mode to the intelligent mode. UWB (Ultra Wide Band), as an emerging wireless communication technology, is gradually making a name for itself in the field of visitor management machines with its unique technical advantages, bringing new solutions and experiences to visitor management.

II. Overview of UWB Technology

(1) Definition and Principle of UWB Technology
UWB technology is a wireless communication technology that uses nanosecond to microsecond non-sinusoidal narrow pulses to transmit data. It does not rely on traditional sinusoidal carriers but realizes information transmission by sending and receiving pulse signals with extremely short durations (usually less than 1ns). The bandwidth of these pulse signals is extremely wide. According to the definition of the US Federal Communications Commission (FCC), the UWB bandwidth needs to be 25% higher than the center frequency or greater than 1.5GHz. When working, the pulse sequence sent by the UWB device is modulated, carries user information, and is transmitted through the antenna; the receiving end uses a correlator to calculate the received signal with the locally generated synchronous pulse sequence, so as to demodulate the original information.

(2) Development History of UWB Technology
The origin of UWB technology can be traced back to the 1940s, when the patent of the random pulse system laid the foundation for its development. In the 1960s, the US military took the lead in applying UWB technology to radar, positioning, and communication systems. In 1989, the US Department of Defense officially proposed the term "ultra-wideband". In 2002, UWB technology was approved by the FCC for use in civil communications, and since then, the application research and development in the civil field have been accelerating continuously. In 2003, the US and European standards for UWB were released, marking a new stage in the development of UWB technology. As time goes by, the International Telecommunication Union (ITU) approved the global regulatory standard recommendations for UWB, the ISO adopted the MB-OFDM standard submitted by the WiMedia Alliance, and the IEEE also continuously updated the relevant standards of UWB, promoting UWB technology to gradually mature and be widely applied in various fields.

(3) Characteristics and Advantages of UWB Technology
High-precision positioning: UWB technology can provide centimeter-level positioning accuracy, which benefits from the characteristics of its ultra-short pulse signals. Compared with traditional positioning technologies, UWB can achieve precise positioning in complex indoor environments, effectively solving the problem of weak or no signals of positioning technologies such as GPS indoors. For example, in large office buildings, shopping malls and other places, UWB technology can accurately track the location of visitors, providing strong support for guiding visitors to their destinations.
Strong anti-interference ability: UWB signals are transmitted using an extremely wide frequency spectrum, and the power spectral density of the transmitted signals is low, and it is not sensitive to channel fading. In a multipath propagation environment, UWB signals can effectively resist signal interference and reflection through a unique pulse sequence design, ensuring the stability and reliability of communication. This gives UWB technology significant advantages in visitor management scenarios with dense personnel and complex electromagnetic environments.
High security: The energy of UWB signals is dispersed within an extremely wide frequency band range. For general communication systems, UWB signals are similar to white noise signals, and the power spectral density is often lower than the natural electronic noise. Therefore, it is extremely difficult to detect UWB pulse signals from electronic noise, which greatly improves the security of communication. In visitor management, it can effectively prevent information from being stolen or tampered with, and ensure the security of visitor information and the stable operation of the system.
Low system complexity: The UWB system does not require the up-conversion process necessary for traditional transceivers, nor does it require complex components such as power amplifiers and mixers. The receiver can directly complete signal detection using relevant devices, greatly simplifying the circuit design of the transceiver and reducing the system complexity. This not only helps to reduce the cost of equipment but also improves the stability and reliability of the equipment, making it easier to be integrated and applied in visitor management machines.

III. Application Scenarios and Function Realization of UWB Technology in Visitor Management Machines

(1) Precise Positioning and Real-time Track Tracking
In large office parks, convention and exhibition centers and other places, visitors are often unfamiliar with the internal environment and are prone to getting lost. The visitor management machine equipped with UWB technology can obtain the location information of visitors in real time by issuing UWB positioning tags to visitors, and present the real-time tracks of visitors in the management system. Managers can intuitively see the movement routes of visitors within the area. Once the visitors deviate from the preset route or enter restricted areas, the system can immediately issue an alarm to achieve precise control of the visitors' actions. For example, in a large exhibition, the organizer can use the UWB visitor management machine system to quickly understand the stay time and movement tracks of visitors at each booth, providing data basis for optimizing the exhibition layout and exhibit display.

(2) Quick Identity Verification and Permission Management
When visitors arrive at the visitor management machine and register their identities by swiping their ID cards, face recognition, etc., UWB technology can quickly interact with the identity recognition system of the visitor management machine. On the one hand, the UWB tag can store some information of visitors, such as appointment information, access rights, etc., and compare and verify it with the identity information read by the visitor management machine to improve the accuracy and efficiency of identity verification. On the other hand, according to the identity and appointment situation of visitors, the system automatically assigns corresponding access rights to control the areas that visitors can enter. For example, in an enterprise park, external visitors can only enter the designated reception areas and meeting rooms, while partners can be granted temporary access rights to specific office areas according to the needs of cooperation projects, ensuring that the activity ranges of different visitors in the park are reasonably controlled.

(3) Visitor Guidance and Intelligent Navigation
With the help of the precise positioning function of UWB technology, the visitor management machine can provide personalized guidance services for visitors. After the visitors complete the registration, the screen of the visitor management machine or the associated mobile application can generate the best route navigation from the current location to the destination, and guide the visitors to their destinations in real time through voice, maps, etc. During the navigation process, the system will dynamically adjust the navigation information according to the real-time location of the visitors to ensure that the visitors can always receive accurate guidance. For example, in a hospital with a complex internal structure and many departments, patients and their families, as visitors, can quickly find the registration office, consulting rooms, examination departments and other destinations through the guidance of the UWB visitor management machine system, greatly improving the medical experience.

(4) Data Statistics and Analysis
The UWB visitor management machine system can collect a large amount of data related to visitors, such as the number of visitors, visit time, stay duration, movement tracks, etc. Through in-depth analysis of these data, the managers of the place can obtain rich information. For example, understand the rules of visitor flow at different time periods to reasonably arrange reception personnel and resources; analyze the attention of visitors to different areas to provide a reference for optimizing the spatial layout and services; evaluate the effect of specific activities or promotions and adjust the operation strategy according to the feedback of visitor behavior, etc. Taking a shopping mall as an example, by analyzing the data of the UWB visitor management machine system, the managers of the shopping mall can understand the stay time and shopping routes of customers in each store, so as to optimize the store layout and product display, and improve customer shopping satisfaction and the overall operation efficiency of the shopping mall.