Use of frequency response masking technique in designing A/D converter for SDR.
Sibongiseni Elliot. Phakathi · ResearchSpace (University of KwaZulu-Natal) · 2005
Analog-to-digital converters (ADCs) are required in almost all signal processing and communication systems.They are often the most critical components, since they tend to determine the overall system performance.Hence, it is important to determine their performance limitations and develop improved realizations.One of the most challenging tasks for realizing software defined radio (SDR) is to move ND conversion as close to the antenna as possible, this implies that the ADC has to sample the incoming signal with a very high sample rate (over 100 MSample/s) and with a very high resolution (14 -to -16 bits).To design and implement AID converters with such high performance, it is necessary to investigate new designing techniques.The focus in this work is on a particular type of potentially high-performance (high-resolution and highspeed) analog-to-digital conversion technique, utilizing filter banks, where two or more ADCs are used in the converter array in parallel together with asymmetric filter banks.The hybrid filter bank analog-todigital converter (HFB ADC) utilizes analog filters (analysis filters) to allocate a frequency band to each ADC in a converter array and digital synthesis filters to reconstruct the digitized signal.The HFB improves the speed and resolution of the conversion, in comparison to the standard time-interleaving technique by attenuating the effect of gain and phase mismatches between the ADCs.Many of the designs available in the literature are compromising between some metrics: design encouragement, motivation and constructive criticism as my supervisor for the last two years.His patience and support have been greatly appreciated.Secondly, a great thanks is owed to my savior, redeemer, deliverer, LORD Jesus.For his enduring love, patience, encouragement and support, he showed me not only over the past two years, but throughout my tertiary education.Thirdly, a great thanks is also owed to my family (Siyabonga, Lindiwe, Hlengiwe, Thando and Mzwandile), my brothers and sisters in the LORD for their