Mobility is an undeniable and unstoppable trend. It is the driving force behind wireless connectivity, allowing people to be connected to information and entertainment whenever they want, wherever they go. The applications for wireless connectivity are virtually limitless — from cell phones, laptop computers and personal digital assistants (PDA) to restaurants, automobiles and even airplanes. Over the last decade, staying mobile and connected has become a way of life.

Fig. 1  Compared with cellular phones from 1995, today's handsets are roughly five times smaller and have far greater capabilities.


As the world’s highest volume consumer electronics product, the cellular phone is a leading driver of mobility and wireless connectivity. Recent statements made by handset manufacturers and industry analysts estimate that the global handset market totaled approximately 630 million units in 2004. For 2005, industry participants are currently forecasting handset unit growth of approximately 10 percent. That equates to roughly 700 million handsets in 2005.

Today’s cell phone has evolved into a multifunctional computing device, incorporating features such as Web access, MSM, e-mail capabilities, video and still cameras, MP3 players, FM radios, and even television tuners (see Figure 1). To enable the trend toward greater functionality and provide more value to consumers, handset manufacturers are focusing their design resources on making phones smaller and more cost effective, increasing performance, and, at the same time, providing larger screens. In turn, this trend is driving innovation and integration within both the wireless world and the wireless semiconductor industry.

In other words, while handset manufacturers are focusing their resources on providing greater functionality to the consumer, they are also requiring wireless semiconductor suppliers to increase engineering responsibility within the cell phone and provide more highly integrated radio system solutions. Hence, those wireless semiconductor manufacturers with deep engineering resources and broad product portfolios are quickly evolving from providers of discrete RF components to strategic suppliers of radio system solutions across the world’s major wireless protocols.

Fig. 2  The evolution of PowerStar PA modules with integrated power control.

A Look Back

In the early 1990s the advent of cellular phones enabled individuals to make voice calls without being tethered to a specific location. At that time, cellular phones contained hundreds of discrete RF components, like power amplifier (PA) microwave monolithic integrated circuits (MMIC), which wireless semiconductor manufacturers supplied and the engineering teams at the handset manufacturers integrated onto the phone board.

The PA is one of the most critical components in the radio section of a cell phone and provides the amplification necessary to transmit a cell phone’s signal to the base cell site. To design an optimal-performing PA, RF Micro Devices in 1991 led the commercialization of gallium arsenide heterojunction bipolar transistor (GaAs HBT) process technology. Using GaAs HBT, the company designed cellular PAs that could operate at higher frequencies and with better power efficiency, gain and linearity than conventional silicon-based semiconductors, making them ideal for high frequency wireless applications.

As the demand for cell phones grew rapidly, so too did the demand for smaller size, longer battery life and lower cost. Soon, handset manufacturers began incorporating higher resolution screens and a variety of synergistic features into the cell phone, and, with the advent of next-generation air interface standards such as GPRS, these cell phones also offered consumers data transmission and wireless web access. The cell phone was beginning to evolve into a multifunctional handheld computing device. These advancements opened a world of opportunities to consumers and handset manufacturers and wireless semiconductor suppliers.

From MMICs to Modules

As the cell phone evolved into a multimedia device providing higher data rates across new air interface standards, its design complexity increased, as did the engineering burden to handset manufacturers. Leading wireless IC manufacturers were able to address this issue by leveraging their internal design resources to provide more highly integrated solutions. One such solution was the multichip, dual-band power amplifier module with integrated power control, a subsystem solution that arrived in the Fall of 2001. These PA subsystem solutions eliminated components, reduced costs and enabled handset manufacturers to accelerate their products to market. The first company to pioneer this solution was RF Micro Devices, with its PowerStar® PA modules (see Figure 2) with integrated power control. Today, the company’s PA modules power one out of every two cell phones made in the world. These highly integrated products provide improved layout and decreased size implementation.

Multichip PA modules quickly overtook the PA market, and today they comprise the majority of PAs sold. Module technology provided an immediate benefit to handset manufacturers, who quickly adopted PA modules as the solution of choice for their cellular phones. These highly integrated products, which are capable of containing multiple ICs in a single package, replaced many single-die RFICs in multiband, multimode wireless devices. For example, a dual-band PA module with integrated power control reduced handset complexity by replacing two PA ICs as well as numerous other passive components with a more elegant single-placement package (see Figure 3).

Using low cost, reliable substrate packaging materials, RF design engineers combined the appropriate die or active circuitry with both large- and small-value passive components for biasing, load line and matching circuits into an increasingly smaller solution. With this technology, leading wireless semiconductor manufacturers delivered self-contained products that reduce board area.

Today’s Competitive Landscape

The drive for innovation and integration — smaller, cheaper, enhanced functionality and less power consumption — is on the rise. Today’s cell phones have truly evolved into wireless handheld computing devices incorporating multiple advanced features. Design complexity is at an all-time high and so are the opportunities for wireless semiconductor manufacturers to provide additional system solutions into the handset.

Fig. 3  Wireless semiconductor suppliers evolve from designing discrete components to designing complex module products that incorporate multiple passive and bias components into a single die, providing significant reductions in size.

Beyond the PA, a similar transformation is occurring within the RF transceiver section of the cell phone. To accommodate the aforementioned increased emphasis on form factor, cost and performance, handset manufacturers have begun to outsource the RF transceiver implementation to external wireless semiconductor suppliers. This has proven a windfall opportunity for wireless semiconductor manufacturers with RF system capabilities and deep design resources.

Leveraging a Trend

Currently, one of the industry’s greatest growth drivers is the migration from GSM/GPRS to Enhanced Data for GSM Evolution (EDGE). At the carrier level, more than 100 wireless carriers are committed to offer EDGE networks, and already more than 30 carriers have launched EDGE services. Research shows that the EDGE market was on track to ship more than 40 million EDGE-enabled handsets in 2004. According to a recent study by industry research firm, InStat, EDGE-enabled phones are expected to account for nearly a quarter of the GSM handsets produced worldwide by the end of 2005, and close to 50 percent by 2007. RFMD foresaw this coming technology shift years ago and pegged it as an entry point into the growing merchant transceiver market.

Fig. 4  Block diagram of the POLARIS TOTAL RADIO™ solution, which employs a low power polar modulation architecture.

Development of the company’s GSM/GPRS/EDGE POLARIS™ TOTAL RADIO™ transceiver solutions began in 2000. The POLARIS EDGE solution (see Figure 4), which includes a PowerStar PA module, provides EDGE functionality with fewer components than competing approaches through the use of an innovative deployment of polar modulation. Additionally, the PA and transceiver are optimized to work together, thereby lowering the bill of materials (BOM) cost and providing longer battery life. With its innovative transceiver solution, RFMD quickly became the first supplier of merchant radio transceivers to ship one million cellular EDGE transceiver chipsets.

Wireless semiconductor manufacturers are also applying low cost module technology to the RF transceiver section. For example, a transceiver module may include the silicon transceiver, SAW filters, matching components, bypass capacitors, simple filters and load inductors, all of which are integrated into a single-placement, space-saving package. This evolution represents a shift in value to wireless semiconductor suppliers, as they take on greater engineering responsibility as well as greater responsibility for the functionality, reliability, test and yield of the product.

The Technology Behind Feature-rich Handsets

o streamline and accelerate the design process of advanced, feature-rich handsets, wireless semiconductor manufacturers continue to develop highly integrated, self-contained module system solutions. Research indicates that multiple radios, including cellular, Bluetooth wireless technology, WLAN and GPS, will populate future wireless devices, including cell phones and laptops. It is increasingly likely that handset manufacturers and makers of other wireless electronics will continue to tap their semiconductor suppliers to enable and accelerate this proliferation of radios. RFMD has positioned itself to accelerate the proliferation of radios through its complementary offerings of Bluetooth, wireless LAN and GPS technologies.

For example, in Bluetooth, the company has designed CMOS system-on-chip solutions for use in cellular phones as well as wireless headsets and various personal computing applications. In WLAN, the company is developing system solutions for the coming PCI Express form factor as well as single-chip system solutions for cell phones. Its GPS offerings include GPS receivers that can be found in multiple cell phone platforms.

To remain competitive, leading wireless semiconductor manufacturers are offering system solutions that are smaller and offer improved performance, reduced BOM costs and increased efficiency. Certain wireless suppliers have gone one step further by broadening their product portfolios beyond cellular. RF Micro Devices, for example, is leveraging its PA market leadership to sell its customers not only RF transceiver system solutions but also additional complementary radios (Bluetooth, WLAN and GPS, for example) for next-generation handsets. This strategy aims to tap into the ongoing consolidation of market shares as procurement teams at handset manufacturers narrow their supply chains to include only strategic wireless semiconductor manufacturers.

Among the leading wireless semiconductor suppliers, the opportunities for growth are broadening. The macro trend toward mobility is undeniable, and wireless connectivity is nothing less than a way of life in both the enterprise and the home. Therefore, the ability to supply highly integrated system solutions across multiple radio protocols helps ensure that, like the world’s wireless consumers, leading wireless semiconductor suppliers will remain on the move. n

RF Micro Devices,® RFMD® and POLARIS™ TOTAL RADIO™ are trademarks of RFMD LLC. BLUETOOTH is a trademark owned by Bluetooth SIG Inc., US, and licensed for use by RF Micro Devices Inc.

Jerry D. Neal is executive vice president of marketing and strategic development and co-founder of RF Micro Devices. After obtaining his college education at Gaston Technical Institute and North Carolina State University, he continued his education in the area of computer technology during his employment with Hewlett-Packard. An entrepreneur at heart, he founded Moisture Control Systems, which he later sold to Hancor Inc. Prior to co-founding RF Micro Devices, he broadened his exposure to sales and technical business aspects at Analog Devices. He has over 30 years experience in the RF and wireless industry.