This article introduces a DPD (digital power detector) based RF front-end design method which can effectively suppress the noise and interference of the DPD loop, improve the dynamic range of the RF front-end, and reduce the cost.
The paper discusses the challenges of designing feedback receivers for Digital Predistortion (DPD) systems used to improve Power Amplifier (PA) efficiency. It highlights that while DPD algorithms are critical, the analog receiver design is equally demanding due to requirements for high linearity and wide bandwidth.
To address these challenges, Linear Technology introduces the LTM9003 pModule receiver. This fully integrated device combines a high-linearity active mixer, an IF amplifier, an LC bandpass filter, and a high-speed ADC into a single 11.25mm x 15mm package. The document details its performance characteristics, including low noise figure and excellent passband flatness, demonstrating how it simplifies board layout and reduces engineering time.
| Package Dimensions | 11.25mm x 15mm |
|---|---|
| Supply Voltage | 3.3V and 2.5V |
| Power Consumption | about 1.5W |
| ADC Sample Rate | 245.76MHz |
| Intermediate Frequency (IF) | 184.32MHz |
It enables digital predistortion by providing accurate RF feedback to reduce crest factor and allow the power amplifier to run closer to saturation.
The device requires a circuit board area of only 11.25mm x 15mm.
The entire chain consumes about 1.5W from a 3.3V and a 2.5V supply.