RF gain control in direct conversion receivers
نویسندگان
چکیده
This paper presents a study of LO selfmixing and RF gain control issues in direct conversion receivers. In cellular systems, that use continuous time frequency duplexing, these can constitute serious problems. The presented topic is of special importance when digitally programmable gain is implemented at the RF frequencies before the downconversion mixers, practically in the LNA. Furthermore, this paper gives circuit solutions to overcome this problem.
منابع مشابه
Receiver Architectures
Topics 1. Main analog components for receivers-amplifiers-filters-mixers-oscillators 2. Receiver architectures and their properties-superheterodyne principle-direct conversion-DC offsets as a challenging problem-low IF, Weaver-effects of I/Q imbalance 3. Non-idealities and performance meatrics of the analog front-end modules-sensitivity, dynamic range-noise figure-intermodulation distortion, IP...
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