Injection-locked Quadrature Oscillator Research Articles

An Injection Frequency-Locked Loop—Autonomous Injection Frequency Tracking Loop With Phase Noise Self-Calibration for Power-Efficient mm-Wave Signal Sources

This paper presents a fast and autonomous injection frequency tracking and locking technique. In the present injection-locking system, a quadrature injection-locked oscillator (QILO) is third harmonically locked to a quadrature voltage-controlled oscillator (QVCO). In the frequency tracking loop, the frequency difference between QVCO and QILO is extracted using the QILO’s amplitude modulated (AM) envelope waveform. The AM frequency of the envelope signal bears frequency difference between the two oscillators. The envelope signal is further converted to pulse signal which subsequently drives digital feedback control circuitry to update the QILO’s output frequency so that it can track the third harmonic of the injection QVCO. The frequency calibration process is purely autonomous, self-initiating whenever the AM modulated envelope waveform is generated. The feedback signal is primarily processed in the digital domain, resulting in a compact, fast, and power-efficient injection frequency-locked loop (IFLL). By incorporating a phase noise (PN) calibration routine after completing the frequency calibration, the presented IFLL resolves the intractable issue of PN degradation at the edge of the slave oscillator’s injection locking range. This results in a large injection frequency tracking range of 26.5–29.7 GHz which is only limited by the QILO’s LC tank tuning range. The IFLL realized in 0.13- $\mu \text{m}$ CMOS consumes 2.4 mW with a negligible area penalty. Overall chip size including QVCO, QILO, and IFLL is $1 \times 1$ mm2.

A Low-Power Low-Noise mm-Wave Subsampling PLL Using Dual-Step-Mixing ILFD and Tail-Coupling Quadrature Injection-Locked Oscillator for IEEE 802.11ad

This paper presents a low-power low-noise 60 GHz frequency synthesizer using a 20 GHz subsampling phase-locked loop (SS-PLL) and a 60 GHz tail-coupling quadrature injection-locked oscillator (QILO) which results in a lower in-band phase noise and out-of-band phase noise, respectively. To save battery life, dual-step-mixing injection-locked frequency divider (ILFD) enhances locking range for high division ratio. Moreover, tail cross-coupling technique in a QILO helps boost negative transconductance $({{-g}}_{m})$ of the 60 GHz QILO which allows the use of larger inductance for power reduction. Implemented in 65 nm CMOS, it can cover required channels from 58.32 to 64.80 GHz with quadrature outputs. It consumes 24.2 and 7.8 mW from 20 GHz SS-PLL and QILO, respectively. The proposed synthesizer achieves $-78.5\; \text{dBc/Hz}$ at 100 kHz offset, $-122\text{dBc/Hz}$ at 10 MHz offset, and a figure-of-merit (FoM) of $-236\text{dB}$ .

A 60-GHz 16QAM/8PSK/QPSK/BPSK Direct-Conversion Transceiver for IEEE802.15.3c

This paper presents a 60-GHz direct-conversion transceiver using 60-GHz quadrature oscillators. The transceiver has been fabricated in a standard 65-nm CMOS process. It in cludes a receiver with a 17.3-dB conversion gain and less than 8.0-dB noise figure, a transmitter with a 18.3-dB conversion gain, a 9.5-dBm output 1 dB compression point, a 10.9-dBm saturation output power and 8.8-% power added efficiency. The 60-GHz frequency synthesizer is implemented by a combination of a 20-GHz PLL and a 60-GHz quadrature injection-locked oscillator, which achieves a phase noise of -95 dBc/Hz@l MHz-offset at 60 GHz. The transceiver realizes IEEE802.15.3c full-rate wireless communication for all 16QAM/8PSK/QPSK/BPSK modes, and the communication distances with the full data rate using 2.16-GHz bandwidth, measured with an antenna built in the package, are 2.7-m (BPSK/QPSK) and 0.2-m (8PSK/16QAM). The measured maximum data rates are 8 Gb/s in QPSK mode and 11 Gb/s in 16QAM mode over a 5 cm wireless link within a bit error rate (BER) of <;10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-3</sup> . The transceiver consumes 186 mW from a 1.2-V supply voltage while transmitting and 106 mW from 1.0-V supply voltage while receiving. Both transmitter and receiver are driven by a 20-GHz PLL, which consumes 66 mW, including output buffer, from a 1.2-V supply voltage.

A Low Phase Noise Quadrature Injection Locked Frequency Synthesizer for MM-Wave Applications

This paper proposes a 60 GHz quadrature PLL frequency synthesizer for the IEEE802.15.3c with wide tuning range and low phase noise. The synthesizer is constructed using a 20 GHz PLL that is coupled with a Quadrature Injection Locked Oscillator (QILO) as a frequency tripler to generate the 60 GHz signal. The 20 GHz PLL generates a signal with a phase noise that is lower than -105 dBc/Hz using tail feedback to improve the phase noise while having a 17% tuning range. The proposed 60 GHz QILO uses a combination of parallel and tail injection to enhance the locking range by improving the QILO injection efficiency at the moment of injection and has a 12% tuning range. Both the 20 GHz PLL and the QILO were fabricated as separate chips using a 65 nm CMOS process and measurement results show a phase noise that is less than -95 dBc/Hz@1 MHz at 60 GHz while consuming 80 mW from a 1.2 V supply. To the author's knowledge this phase noise is about 20 dB better than recently reported QPLLs and about 10 dB compared to differential PLLs operating at a similar frequency and at a similar offset.

Frequency-Hopped Quadrature Frequency Synthesizer in 0.13-$\mu$m Technology

This paper presents a Wireless-USB/WiMedia-compliant fast-hopping frequency synthesizer architecture with quadrature outputs based on sub-harmonic injection-locking. The synthesizer features a cross-coupled quadrature digitally-controlled oscillator, that is injection-locked to a sub-harmonic frequency. An intuitive closed-form expression for the dynamics of the quadrature injection-locked oscillator and a technique to achieve fast frequency-hopping, are presented. The overall architecture, based on this technique, is a CMOS-only implementation and has been fabricated in a 0.13-μm SiGe BiCMOS process. On-chip mixers have been implemented to measure the quadrature accuracy of the outputs. Measurement results indicate lock-times of less than 2.5 ns, a locked phase noise of -114 dBc/Hz at 1 MHz offset and a quadrature accuracy of better than 0.5°. The frequency synthesizer (excluding output buffers) occupies an area of 0.27 mm2 and consumes 14.5 mW of power. The best and worst case spur suppression achieved are 47 and 31 dB, respectively. This is the lowest power fast-hopping quadrature frequency synthesizer that has been reported to date.