RF Power Amplifier Market Analysis

Competitive Landscape for 802.11b/g/a Power Amps - February 6, 2005
We have two issues with statements recently made by ParkerVision. ParkerVision’s claims are as follows:

Claim #1
They will create a significant revenue stream based on sales of their revolutionary power amplifiers.

Claim #2
They have developed higher efficiency power amplifiers (for use in wireless cards for laptop computers), that can significantly extend the battery life of the computer. We all know that battery life of a computer is important, especially for those of us who travel, and can’t finish our customer presentation on a trans-Atlantic flight!

We took issue with these claims, so we spoke with engineers at several reputable power amplifier companies and present here is a brief summary of what we learned.

Claim #1:
Significant Revenue Stream

The market for 802.11x power amplifiers is well known to be fiercely competitive. There are numerous manufacturers of power amplifiers (see links below). Prices are continually eroding while margins are shrinking. For example, a complete module with integrated passive components sells for well under a $1.00 today. Everyone we spoke to expects the pricing to continue to erode faster and further. Therefore, the expected revenue stream of players in this field will diminish with shrinking prices, or at best stay flat if volumes increase. Moreover, the decreasing prices will place stress on the ability of these company to remain profitable.

Claim #2
The efficiency of power amplifiers found on wireless communications cards greatly increases battery life in laptop computers

When we consider how battery power is actually used by a laptop computer, we find that about 80% of it is consumed by the central processing unit (CPU) and the liquid crystal display (LCD) panel. So, at best, the wireless card used for computer communications (in the “local area network” or LAN) consumes 20% of the battery power.

At least half of the power consumed by a wireless LAN card is used by its digital signal processor (DSP) chip for signal processing of the information transmitted and received by the card. The other 50% goes to the transmitter of the wireless card, where the power amplified is located. This means that at most 50% of the wireless LAN card power goes to the power amplifier, but only during transmission of information from the computer to the network. Therefore, during transmission, at most 10% of the laptop power is used by the power amplifier.

The remaining question is how often a computer transmits information rather than receives it. The majority of the time, a computer is receiving data. If we image users surfing the Web, for example, they spend most of their time waiting for pages to download (receive information). Once a page is downloaded, they read it (no reception or transmission) and then click on a button or fill in some information. The computer then transmits this data and receives the next page. Similarly, with email, the user receives the data, spends much longer typing the reply, and then sends it. Thus, it is hard to imagine that the wireless LAN transmitter is active more than 25% of the time (more likely 10% of the time).

Therefore, at best, the power amplifier uses 10% of the laptop battery power 25% of the time. In other words, the power amplifier accounts for 2.5% of the laptop batter power consumption. Simply put, the efficiency of power amplifiers found on wireless communications cards makes little or no difference to the battery life of a laptop computer. The net effect is that customers buying wireless cards don’t really care about the efficiency of the power amplifiers used. This is in direct contrast to cell phones, where the power amplifier efficiency is far more important.

Today, wireless LAN power amplifier efficiencies tend to be in the 30% range for 801.11a and 802.11g, and a bit higher (at 40%) for 802.11b. Everyone knows how to get higher efficiencies (we were quoted up to 60% or better). Even if the efficiency were doubled, however, the laptop battery life would only increase by about 1%. This improvement is not sufficient to be a market driver for a new power amplifier, let along to justify an investment of millions of dollars to develop one. They key market drivers at this point for wireless cards are price.

They key driver for power amplifiers is therefore a reduced manufacturing cost. As in cellular power amplifier modules, the packaging costs of the module are comparable to the die cost, while the “packaging-plus-test” costs are larger than the die cost. This means that the overall power amplifier manufacturing costs cannot be reduced by simply reducing the die size (and hence cost). Moreover, the industry already uses very tiny die sizes for wireless power amplifier products, mostly in the range of 1 mm2 to 1.5 mm2. Huge numbers of die per wafer are already being produced, so there is minor advantage to be found through further miniaturization. There are advantages to be had, however, by moving the manufacturing facilities to Asia, where labor is much less expensive.

The links below lead to companies that are active in the wireless power amplifier market. We present examples of part numbers, typical performance (specifically efficiency), and data sheets. Note that nearly all of the products here have been available for a year or more. No future products are included in this list.