The horizontal effect: modular versus integrated wireless design

The new paradigm has triggered a dramatic shift in the approach to wireless handset design. Given that handsets remain the primary engine for wireless connectivity development, these changes should become industry-wide and spill over into the newer, less mature segment of wireless-enabled devices.

Traditionally, major wireless handset players such as Motorola, Ericsson, and Siemens have handled design and production in-house. Increasingly, however, these players have turned to outsourcing of design and production to keep their products up-to-date and cost-competitive. The primary benefit of this strategy is cost reduction: design and development shops amortize the fixed costs of development over a broader product range and customer base, lowering costs for all. This is the structure that has kept the PC industry operating profitably — if only marginally, recently — for over two decades, with companies like Intel, ATI, and large contract manufacturers amortizing development costs and capital expenditures over a range of OEMs.

This has created a tremendous opportunity for design and development houses, mainly in Asia, to provide mobile applications. However, the challenge is to take a product that has typically been designed via an integrated approach (in-house teams collaborating on virtually all aspects of product design and development) and re-architect it in a way that various components of the overall solution (applications, software, chipset,), provided by a handful of specialized companies, can be integrated easily, cost-effectively and reliably.

Without a strong mobile application development platform, wireless OEMs lose in time and reliability what they might save in up-front cost.

A new approach is a modular design with open interfaces to a wireless module on the one hand and an application module on the other. This approach, which we've called "dual-function architecture", dramatically simplifies the contributions of design houses, application developers and contract manufacturers to the production of a wireless handset.

Dual-function architecture includes both a wireless module interface (to a wireless module) and an application interface (to virtually any application module). The specification of these two interfaces means that any reference design motherboard that adopts these interfaces will be able to combine wireless access with application support I/O functions for voice, data and audio. This is a simple, feature-rich and versatile reference design that has widespread applicability as the foundation for various wireless-enabled devices.

A strong approach to dual-function architecture is through the development of a low-profile wireless module, which includes the antenna connection as well as all required interfaces to drive the various mobile application device inputs and outputs (keyboard, LCD, SIM card, audio, and GPIOs). Coupled with an open MMI/API software development platform, this configuration enables system designers and developers to build customized MMI (man-machine interface) efficiently and build/port customized applications easily over an API platform.

Deploying connectivity
Most importantly, by starting with wireless module development, wireless design houses start with a building block that can easily be redeployed beyond handsets to other devices requiring wireless connectivity. By integrating RF design and wireless protocol in a module, non-handset devices need only integrate a wireless module interface in their reference design. The result is extremely cost-effective and reliable, particularly given the module supplier's ability to amortize wireless module development over a broad customer and product base.

A key business factor to consider in module development — and evaluating modular solutions — is ensuring full wireless connectivity without additional design work. The main advantage of the modular approach is ease of integration by partners with limited wireless expertise, such as device designers seeking wireless connectivity and contract manufacturers. In addition, true modular architecture enables designers to add new features quickly and easily in the reference design or via an application module interface with minimal or no changes to the pc board design, speeding time-to-market. Through a modular approach, product design and development begins to resemble a simple integration job. This is a crucial advantage.

It's also important to ensure that modules are designed with an open API and customizable MMI in mind. Designers of end-products need to be able to customize the look and feel of the device to their own specifications in order to strengthen their brands. Engineers need to be cognizant of this key business reality.

Meanwhile on a highly practical level, size matters. In electronics design and manufacturing product evolution tends towards miniaturization. Wireless modules, while cost-effective and highly reliable, involve a thickness that may impact end-product design, or make a modular solution simply unfeasible.

In cases where wireless connectivity is needed and there are extreme form factor requirements, an integrated wireless development approach might still be the only option. A median solution that would capture some of the benefits of outsourcing would be to partner with a wireless design house to integrate elements of a wireless module directly on the motherboard.