Parkervision's D2D Technology Supports Digital Cellular Communications
CDMA is the fastest growing digital cellular standard in many regions and is now widely accepted as the foundation for the competing third generation (3G) wireless standards. CDMA is considered to be the most demanding of the current digital cellular standards in terms of radio frequency performance requirements. The company believes it is a significant accomplishment to address this specification using a standard CMOS semiconductor while simultaneously creating a true Zero Intermediate Frequency (IF) architecture.
The D2D CDMA transmitter demonstrator exceeds key performance requirements of the IS-95 CDMA standard including a typical Rho of 0.9967, typical ACPR met with a 3 dB to 5 dB margin, and no additional baseband processing or DAC speed/resolution required.
Doug Makishima, Director of Marketing and Business Development -- Cellular Industry, commented, "The D2D architecture achieves the highest linearity per milliwatt of power consumed of any radio technology of which we are aware, and does this in a very cost-effective manner. The local oscillator in a D2D-based implementation will typically operate at one third or less of the RF carrier frequency. Since D2D uses a subharmonic clock, implementations do not require synthesizers operating at or near the RF frequency as with traditional radio architectures. This provides lower power, higher performance solutions that effectively reduce noise and design issues that are inherent in traditional or other direct conversion designs which require the use of local oscillators operating at or near the RF frequency. This is one of the reasons that our technology lends itself to full integration in standard CMOS and allows D2D-based radio hardware to take full advantage of Moore's Law regarding semiconductors."
ParkerVision announced that an application note with complete technical details should be made available within two weeks. They are also currently developing a prototype D2D-based CDMA receiver demonstrator. The company's analysis shows that D2D can also meet or exceed CDMA IS-95 receiver specifications. The company is also working with a number of companies to develop an RF-to-baseband interface specification for D2D-based CDMA radios. The company intends to develop integrated radio frequency transceiver ICs targeted at the IS-95 CDMA standard as well as other cellular standards based on its D2D technology.