MOS-only design automation and a simple agile MOS-only BP/LP filter design
In this work, a systematic of the automation in the result of the re-obtained small signal parameters based on SPICE is presented for MOS-Only circuits. Accuracy of the re-obtained parameters was improved by re-formulating in the basis of SPICE and CADENCE-SPECTRE. Moreover, piece-wise polynomial regressive models are presented for gds, gm and Ids-Also, performance of the models are compared with conventional expressions. Success of the given MOS-Only design automation based on re-obtained small signal parameters is verified with an examplary new agile filter.
Realization of CDTA based frequency agile filter
This paper presents frequency agile filter based on current difference transconductance amplifier (CDTA). The agile filters used in this work provide high agilty, tunability and quality factor while they are fully integrated configurations and not discrete systems. The use of grounded capacitors and resistor makes these structures suitable for integration. The functional verification is exhibited through extensive SPICE simulations using 0.25μm TSMC CMOS technology model parameters. The performance evaluation is made in terms of power dissipation, signal to noise ratio (SNR) and output noise.
Frequency agile RF filter for interference attenuation
This paper introduces a frequency agile RF filter for interference attenuation in a base station RF frontend. Digital and RF systems are combined in a feed-forward architecture. This architecture provides a frequency response with multiple tunable transfer function zeros. This feed-forward architecture is called the hybrid RF-DSP feed-forward filter. Measurements demonstrate successful interferer suppression for operation at several bands between 800 and 1800 MHz. The group delay mismatch between the feed-forward paths is reduced with a delay line to achieve between 32 to 24 dB of attenuation for interferers with bandwidths from 1 to 8 MHz. The digital filter used within the prototype had 32 complex taps, thereby providing the RF filter with 32 tunable transfer function zeros.