Variable Sample Rate Conversion Techniques for the Advanced Receiver

One of the primary challenges in the development of the Advanced Receiver is the ability to accommodate a wide variety of possible data rates, motivated by the desire to support different missions for the Deep Space Network (DSN) under different adverse conditions. To conform to fixed architectures such as the analog-todigital converter (ADC) used at the front end and tracking loops used subsequently, this requires that the sampling rate be varied entirely digitally after the ADC to accommodate the fixed parameters of the tracking loops. In this article, we present a series of methods to achieve variable sample rate conversion (SRC). Specifically, we focus on two sets of schemes to alter the sampling rate: coarse techniques to lower the bulk of the sampling rate near the desired amount while removing out-ofband artifacts due to noise and interference, and fine techniques used to accurately tailor the sampling rate to the exact desired value. Advantages and disadvantages of both sets of methods are investigated in terms of implementation complexities and performance metrics.