Exploring the next generation of wireless R&D

In 2017 and beyond, the next generation of wireless communications systems is driving a new level of technology integration.

Higher data rates, massive connectivity for systems like the Internet of Things (IoT), lower power consumption and other ambitious goals can only be achieved by combining advanced digital, RF and antenna technologies. Traditionally, each of these components has been designed separately, only to be integrated, tested and debugged after the first hardware prototype is built. The days of this approach, with domain experts working separately, using separate tools, are numbered.

With current technology, the entire signal chain from RF to baseband can be implemented in a single programmable device or module. Consider the expertise required to use, let alone design, one of these devices: RF, digital logic, digital signal processor (DSP), embedded software and system architecture. To integrate it into a complete system, engineers need to know even more: antenna design, propagation and one or more wireless standards.

For example, if an engineer designs baseband algorithms without considering RF impairments, it is unlikely these algorithms will work in the real world. For RF front-end designers, the DSP and digital control algorithms and antenna configuration will affect system performance and cost. When using multiple tools from different vendors, it is difficult to model these component interactions, and it is expensive and slow to test and correct errors, leaving little or no time to optimise the design.

Integrating the workflow

Successful wireless engineering teams understand that in order to keep up with the demands of next-generation wireless systems, they need a more integrated approach. Each team member needs to be a multifunctional engineer who can comfortably work in the digital, RF and system domains.

These teams are adopting tools that help them integrate the multiple engineering disciplines into a coherent workflow. They use an integrated software environment, like the one provided by MATLAB and Simulink, that enables Model-Based Design and encompasses algorithm design, system simulation, over-the-air testing, prototyping and implementation. The improved workflow accelerates delivery of error-free prototypes and products by enabling engineering teams to jointly design and verify algorithms and RF components, perform end-to-end simulations and connect to a range of hardware for testing, prototyping and implementation.

Compared with groups still designing in silos, teams taking advantage of earlier design integration report savings as much as 30% in overall development time and 85% in functional verification time, having dramatically fewer design respins and creating defect-free implementations on the first attempt.

A multifunctional toolbox

A flexible, integrated simulation environment provides critical advantages for wireless system design. Model-Based Design allows engineers to design, model and simulate multidomain wireless systems. Domain experts in each area can use the tool that is best suited to their task, to model RF architectures, digital hardware and complex state machine logic, and then seamlessly connect their own work into the rest of the system.

In order to span this set of tasks, the software must operate at three levels: low-level functions (eg, modulation, mapping, pre-coding) with open interfaces; mid-level functions that process a complete link (physical channels and signals) in one step; and high-level signal generation functions and apps. And it should offer hardware-agnostic testing interfaces, so the generated signals and the test bench can be used for simulation and test hardware independent of a specific manufacturer.

Meeting the demands of the next generation

The tools capable of supporting the work of the multifunctional wireless engineer are already on the market. They are particularly useful for advanced research and design problems, such as modelling multiantenna (MIMO) systems found in LTE and WLAN systems and 5G proposals, including antenna arrays, propagation patterns and beamforming.

As a result, engineers can eliminate steps and deliver working designs faster because they can prove compliance with standards in simulation and over-the-air tests, and explore and optimise system designs with joint baseband-RF simulations. Teams can eliminate design problems before moving to implementation and streamline verification with built-in reference models. Further, engineers can harness these tools to re-use models to speed up design iterations and next-generation projects, allowing them to accelerate the design of next-generation wireless communications systems.

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