Ubiquitous connectivity shapes the future of wireless - What engineers need to know

Connecting people and everything, everywhere, has always been the primary goal of wireless communications. Whether it’s people communicating on their phones, vehicle-to-everything (V2X) platforms helping cars steer in traffic, or Internet of Things (IoT) devices monitoring smart factories, today’s wireless systems are gradually making these dreams a reality.

This powerful force means that ubiquitous connectivity - a system that can seamlessly use satellite, cellular and local area networks to maintain a fast, secure and reliable online connection - is no longer a "nice to have" feature, but a "must have" feature.

For engineers building these technologies, the challenges of designing wireless systems optimized for ubiquitous connectivity grow as ubiquitous connectivity increases. These include ensuring devices comply with standard protocols for system and device interoperability; optimizing multi-domain system parameters for integrated algorithm, antenna, array, and RF transceiver design choices; and validating designs for hardware prototypes with automated wireless testing and realistic channel and impairment models.

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 but also true ubiquitous connectivity for business customers and consumers alike.

Development of wireless technology

From a technical perspective, the concept of ubiquitous connectivity is not new. However, its realization remains a challenge for various reasons, including economic, technical and physical. From an economic perspective, the number of access points has historically been limited by cost and has been mainly deployed in areas with high population density. High-throughput links cannot be built seamlessly at various ranges and distances, and each technology caters to its own niche. Finally, physically, each communication link is also limited by interference from other systems using the same or adjacent spectrum. This makes it necessary to coordinate between the various systems.

While modern advanced wireless systems have overcome many of these challenges—for example, low earth orbit (LEO) satellites are more cost-effective than medium earth orbit (MEO) and geostationary earth orbit (GEO) satellites, and their signals are capable of providing high throughput over long distances—other challenges remain.

For example, 5G, Wi-Fi, and satellite-based communications devices rely on multi-user multiple-input multiple-output (MIMO) beamforming technology to reach users in the service area. Devices that support MIMO and beamforming are able to 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 in conjunction, for example, a signal sent to a crowded cellular service area can spread the workload to 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 low power consumption and use of the ISM band for its Basic Rate, Enhanced Data Rate, and Bluetooth Low Energy standards make the platform an ideal choice for sending short-range signals. Engineers can use the short-range signals provided by Bluetooth because they best indicate whether a device needs to connect to the Internet. Bluetooth can also help engineers save 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 working on these issues, extensive testing is better done through modeling and simulation than using live equipment. Therefore, the value of large-scale simulation platforms is highlighted.

How Simulation Helps Engineers Achieve Ubiquitous Connectivity

To address the challenges of ubiquitous connectivity, engineers must not only understand the relationships and interferences between all of today's wireless communication protocols and standards, but also test the compatibility between these 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 equipment is built.

For example, when developing a cellular network system, 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 for a variety of channel conditions that may occur in a typical cellular network. If all test conditions are not met, the system will not pass certification.

To address this problem, engineers can use simulation platforms to provide an environment that makes reviewing all potential parameters and evaluating other systems easier, faster, and more reliable than physical testing. Faster testing methods are largely possible thanks to technological advances brought about by MATLAB and Simulink, such as the ease of test waveform generation, the use of automatic C code generation, and the use of GPUs and parallel computing in accelerated simulation.

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 pointing 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 testing environments that enable them to see the impact of indoor and outdoor RF propagation on a map. This will help them ensure accurate connections between multiple devices.

Ubiquitous connectivity remains a must in the modern world. This ultimately means that simulation platforms must also adapt to meet the requirements of engineers as they design systems that can seamlessly use multiple modes, including satellite, cellular and local area networks, while maintaining fast, secure and reliable online connections.

#Article copyright MathWorks#