| Direct2Power(D2P) Analysis |
Several issues exist with statements recently made by Parkervision about its new D2P variation of ESP technology. ParkerVision's claims are as follows: Claim #1: D2P chips will create a significant revenue stream
based on sales of their revolutionary power amplifiers In an analysts' call on January 30, 2005, ParkerVision CEO Jeff Parker explained that power, consumed by heat loss, is a key challenge to manufacturers of mobile and wireless devices. 802.11g devices typically run at 5 percent efficiency and 802.11b devices typically run in the 8 to 9 percent efficiency range. "This means that 95 percent of all the power it takes to run those circuits goes up in heat. It does not come out the antenna in any usable purpose," Parker said. A brief summary is presented here regarding these claims: Claim #1: Significant Revenue Stream Claim #2: D2P Technology is Novel and Patentable The parts of the patent that describe functioning elements are not novel. What is novel doesn't work The inexperience of the ParkerVision team is evident not only in naivete of the proposed approach, but also in their inability to discover the underlying flaws, despite what is clearly a large effort. If they did discover their flaws in the course of the work, their lack of candor in acknowledging them is itself problematic, particularly in view of past published allegations of fraudulent claims. Claim #3: The efficiency of D2P power amplifiers greatly increases battery life of laptop computers and cell phones
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. ParkerVision claims to be able to be 2-4 better than existing power amps (which they believe to be 5% for 802.11g, and 10% for 802.11b). From this, we conclude that ParkerVision is aiming for 10-20% for 802.11g, and 20-40% for 802.11b. In reality the market is already there, and several companies have had better power amps shipping in volume for a year or more. The fact that ParkverVision either doesn't know about, or ignores these existing parts is hard to understand. 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 no 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. Relevant Links: RF Micro Devices has 25% efficiency for 802.11b/g (RF5117, RF5189,
RF2189, RF2163). SiGe Semiconductor ( SE2520L and SE2522L for 802.11b, SE2523L, SE2525L, SE2528L and SE2529L for 802.11b/g) http://www.sige.com/wireless/se_2520_wlan.html RF Integrated Corporation has 42% efficient 802.11b (22% for 802.11g) (AP1098). http://www.rfintc.com/pdf_file/WLAN1_DM.pdf Maxim has 34% for 802.11b/g ( MAX2244)
Epic Communications has 40% for 802.11b/g (PA2404) |