A 4× Sub-Harmonic Regenerative Divider Based Carrier Recovery Receiver

In this paper, a carrier recovery technique based on the concept of dual loop regenerative LO signal is proposed. The recovery core involves a novel multi-phase 4 ×sub-harmonic mixer based regenerative divider followed by a PLL block. The focus of this receiver is to regenerate the LO signal from the input pilot tone and make the PLL stay in lock with the recovered LO during the multitone input without degrading the overall SNR. The proposed concept alleviates the problem of conventional regenerative divider which suffers from degradation of SNR for muti tone input signal. To test the proof of concept the proposed method is investigated through the circuit level simulations and verilogA model of PLL and the feasibility is examined via the successful down-conversion of the modulated data with the regenerated LO signal with a significant SNR. The proposed carrier recovery receiver is implemented in 28nm CMOS process and simulated for the RF pilot tone of frequency 28GHz and multitone signal bandwidth of 200MHz. The novelty of this method is, it can be used for the receiver working at higher frequencies relaxing the requirements of LO to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1/5^{th}$</tex> (5.6GHz)of the incoming signal frequency.