【Introduction】Connecting people and everything everywhere has always been the main goal of wireless communication. Whether it’s people using cell phones to communicate, vehicle-to-vehicle communication (V2X) platforms helping cars turn in traffic, or Internet of Things (IoT) devices monitoring smart factories, today’s wireless systems are gradually making these dreams a reality.
This power means that ubiquitous connectivity – a system that seamlessly uses satellite, cellular and local area networks to maintain fast, secure and reliable online connections – is no longer a “must have” feature but a “must have” function.
For the engineers building these technologies, the challenges of designing wireless systems optimized for ubiquitous connectivity have grown as the capabilities of ubiquitous connectivity have grown. These include ensuring that devices comply with standard protocols for system and device interoperability; optimizing multi-domain system parameters for integration algorithm, antenna, array, and RF transceiver design choices; and verifying with automated wireless testing and realistic channel and impairment models Design of hardware prototypes.
Fortunately, engineers can use existing technologies and best practices to design, model, and test these systems to ensure they work together to provide not only wireless access to business customers and regular consumers, but true ubiquity connect.
The development of wireless technology
From a technical point of view, the concept of ubiquitous connectivity is not new. However, its realization remains a challenge due to various economic, technological and physical reasons. From an economic point of view, the number of access points has historically been limited by cost, mainly deployed in high-density population areas. High-throughput links cannot be built seamlessly at various ranges and distances, and each technology is catering to its own niche. Finally, each communication link is physically limited by interference from other systems using the same or adjacent spectrum. This necessitates coordination between the various systems.
While many of these challenges have been overcome by modern advanced wireless systems, for example, low earth orbit (LEO) satellites are more cost-effective than medium earth orbit (MEO) and geostationary orbit (GEO) satellites, and their signals can provide high throughput over long distances , but other challenges remain.
For example, 5G, Wi-Fi, and satellite-based communication devices rely on multi-user multiple-input multiple-output (MIMO) beamforming techniques to reach users in the service area. Devices that support MIMO and beamforming can send and receive multiple signals, which requires engineers to optimize the use of multiple frequency bands simultaneously. However, this requires continuous monitoring of the available signal space and precise scheduling, as well as channel modeling and measurements at both ends of the link connecting the two devices.
When designing for ubiquitous connectivity, engineers typically specify Wi-Fi systems for short-range communications and cellular systems for long-range communications. These heterogeneous types of networks can work associatively, for example, a signal sent to a congested cellular service area can spread the workload over the Wi-Fi service network and vice versa.
Bluetooth also plays a role in ubiquitous connectivity. While Bluetooth is not a high-throughput wireless network, the platform is ideal for sending short-range signals due to its basic rate, enhanced data rate, and the low power consumption and ISM band usage of the Bluetooth LE standard. Engineers can use the short-range signals provided by Bluetooth because they are the best indicator of whether a device needs to connect to the Internet. Bluetooth can also help engineers conserve bandwidth and keep devices offline when they don’t need to be connected.
Ensuring that these types of networks (wide area networks such as satellite links, cellular wide area networks such as 4G and 5G, local area networks (Wi-Fi), and personal area networks such as Bluetooth) simultaneously provide ubiquitous connectivity requires extensive testing. For engineers dealing with these issues, extensive testing is better through modeling and simulation than using field devices. Therefore, the value of a large simulation platform is highlighted.
How Simulation Helps Engineers Achieve Ubiquitous Connectivity
To address the challenges posed by ubiquitous connectivity, engineers must not only understand the relationships and interference between all of today’s wireless communication protocols and standards, but also test the compatibility of those standards.
Engineers can use large-scale modeling and simulation tools such as MATLAB and Simulink to design, model, test, and analyze systems before deployment, ensuring that their systems are reliable long before physical devices are built.
For example, when developing cellular network systems, a key challenge is dealing with the number and complexity of parameters associated with each mode of operation. Engineers need to understand that each parameter needs to be tested against the various channel conditions that can occur in a typical cellular network. If all test conditions are not met, the system will fail certification.
To address this, engineers can use a simulation platform to provide an environment that makes reviewing all potential parameters and evaluating other systems easier, faster, and more reliable than physical testing. Thanks to technological advancements brought by MATLAB and Simulink, such as the ease of test waveform generation, the use of automatic C code generation, the use of GPUs and parallel computing for accelerated simulation, and more, faster test methods are largely possible.
Of course, the effectiveness of multi-user MIMO and beamforming systems depends on the ability to accurately point and connect to the target device. This requires simulation platforms such as MATLAB and Simulink to simplify the task of verifying accurate orientation and positioning. These solutions not only provide engineers with industry-standard tools to generate a variety of signals including Bluetooth, 5G, LTE, and Wi-Fi, but also provide visualization and test environments that allow them to map indoor and outdoor RF spread influence. This will help them ensure accurate connections between multiple devices.
Ubiquitous connectivity remains a must for the modern world. This ultimately means that simulation platforms must also be adapted to meet the requirements of engineers, as they design systems that can seamlessly use multiple modalities, including satellite, cellular and local area networks, while maintaining fast, secure and reliable online connections.
