Alena Djugova

A low power 3.1–7.5 GHz tunable pulse generator for impulse radio UWB

A novel energy-efficient tunable impulse radio ultra wide band (IR-UWB) pulse generator (PG) for the high data rate 3.1-7.5 GHz band applications is proposed. Glitch generator, switched ring oscillator, buffer and pulse shaping filter are the key components. The circuit is scalable both in bandwidth and center frequency. The glitch generator combines falling edge of the input signal and its delayed inverse, allowing the impulse duration to be tuned over a wide range (250-660 ps) by varying the delay between the edges. The generated impulse duration approximately defines the PGs signal width and thus its spectrum bandwidth. The ring oscillator frequency, which determines the spectrum center frequency, is controlled by the gate control voltage of the PMOS transistor used as an inverter feedback in the ring oscillator. Post-layout simulations show the pulse amplitude of 261 mV and the pulse duration around 700 ps. The total power consumption is only 697 μW with a supply voltage of 1.8 V. The PG is designed in UMC 0.18μm CMOS technology with the total chip area of 602×587 μm2.

A 2.4 GHz high-gain low noise amplifier

In this work a design of a 2.4 GHz current reuse low noise amplifier (LNA) in a standard 0.35 µm SiGe technology is presented. In order to achieve good input matching for narrow bandwidth the inductive source degeneration LNA topology is used. Low power consumption with higher gain is obtained using current reuse configuration. In order to provide good isolation and stability cascode amplifier, as a part of current reuse topology, is used. For given configuration, good trade-off between low noise, high gain and stability has been achieved. Optimized LNA has −21.18 dB input return loss (S11), high reverse isolation of −47.51 dB (S12), very high voltage gain (S21) of 23.54 dB, −15.93 dB output return loss (S22), noise figure of 2.7 dB, and a power consumption of 5 mA at 3.3 V. The LNA presented offers high circuit stability parameters B1f=979.6 m and K=7.658.

A 3.1 – 6.65 GHz, 933µW impulse radio pulse generator with tuneable spectrum in 0.18µm CMOS

A low-power tuneable impulse radio ultra wide band (IR-UWB) pulse generator (PG) for 3.1 - 6.65 GHz band applications is proposed. To provide compensation due to process, voltage and temperature (PVT) variations and achievement of best performance, the PG is capable of adjusting the Power Spectral Density (PSD) modifying the generated pulse amplitude and duration. Furthermore, the spectrum center frequency can be tuned by changing the frequency of the voltage controlled ring oscillator. Post-layout simulations show the pulse amplitude of 315 mV and the pulse duration around 1 ns. The generated signal spectrum fully complies with the FCC spectral regulations. The total power consumption is only 933 μW with supply voltage of 1.8 V. This corresponds to energy consumption of 11.67 pJ/pulse for a 80 MHz pulse repetition frequency (PRF). The PG is designed in UMC 0.18μm CMOS process with the total chip area of 0.35 μm2.

A 0.18μm CMOS low power LNA for 6–8.5 GHz UWB receivers

This paper presents the design of an ultra-wideband (UWB) low noise amplifier (LNA) in 0.18μm CMOS technology. Proper input matching is achieved with inductive degenerated amplifier circuit modified with resistive feedback. To provide good isolation and stability, cascode amplifier, as a first amplifying stage, is used. Additional common source stage is introduced by using current reuse technique. Operated at 1.8 V LNA consumes only 5.26 mW. The simulation results show maximum power gain of 14.3 dB, while the input and output return loss is less than −10 dB, within the bandwidth from 6 to 8.5 GHz. The noise figure of the LNA varies from 3.9 to 6.8 dB.

Basic figures of merit for A 1.575 GHz low noise amplifier in 0.35 µm SiGe BiCMOS technology

A design of 1.575 GHz two-stage low noise amplifier (LNA) in a BiCMOS 0.35 µm process is presented. First LNA stage is common source amplifier in cascode configuration with source degeneration set for input matching. Additional stage is introduced in order to increase S21 of the LNA. Simulation results for S11, S12, S21 and S22, together with NF, Kf and B1f are given for presented LNA topology.

Compact UWB resistive feedback low noise amplifier utilizing current bleeding technique

In this paper, a low-noise amplifier (LNA) designed for the lower band of the ultra-wideband (UWB) spectrum and implemented in 0.18 μm CMOS process is presented. Post-layout simulations show a power gain (S21) of 11.18 dB with 0.8 dB value variations from 259 MHz to 5 GHz. The input and output return losses, S11 and S22, are below -10 dB from 466.4 MHz to 5.63 GHz, while reverse isolation (S12) is better than -24.44 dB across the whole simulated range, from 100 MHz to 7 GHz. The average value of noise figure (NF) is 4.48 dB, with minimum value of 4.24 dB at 1.37 GHz. The input-referred third-order intercept point (IIP3) and the input-referred 1-dB compression point (P1dB) are -12.72 dBm and -20.9 dBm, respectively. The LNA core area occupies 0.353 mm2 and consumes 11.16 mW from a 1.8 V supply.

A novel low-complexity BPSK IR-UWB pulse generator in 0.13um CMOS technology

A new low-complexity energy-efficient impulse radio ultra-wideband (IR-UWB) pulse generator is investigated in the paper. It is designed and simulated in low-cost 0.13 μm UMC CMOS technology. The spectrum adjustable architecture consists of a tunable glitch generator, a BPSK modulator, two voltage controlled ring oscillators, an output buffer and a shaping filter. The simulation results showed spectrum that covers the higher UWB band and fully complies with the corresponding FCC spectral mask. The pulse duration is around 0.6 ns, and the peak-to-peak amplitude is 380 mV on 50 Ω output load. It has low power consumption of 0.44 mW corresponding to energy consumption of 2.2 pJ per pulse for 200 MHz pulse repetition frequency (PRF).

Inverter-based low-noise amplifier topologies for ultra-wideband applications

In this paper two ultra-wideband (UWB) low noise amplifier (LNA) configurations in UMC 0.18μm CMOS technology are presented. Both amplifiers are based on a shunt-feedback inverter-configuration with inductive peaking. In first LNA topology inductor is placed at the input node of the inverter cell. In the frequency range from 3.1 GHz - 10.6 GHz, this amplifier achieves power gain (S21) of 12.23 dB, noise figure of 5.62 dB and input/output return loss of -8 dB/-11 dB, while consuming 9.61 mA from 1.8 V supply. In second LNA peaking inductor is applied at the gate of NMOS transistor in inverter stage. With this technique the -3 dB roll-off frequency is increased from 9 GHz, obtained with previous technique, to 11.11 GHz, without additional power consumption. Achieved power gain from 3.1 GHz - 10.6 GHz is 12.64 dB, noise figure is 4.04 dB and input/output return loss is -7 dB/-10 dB. This amplifier consumes 9.48 mA from the 1.8 V supply.

A tunable OOK IR-UWB pulse generator in 0.18 µm technology

A new energy-efficient, tunable impulse radio ultra-wideband (IR-UWB) pulse generator is investigated in the paper. The low complexity architecture is composed of a data and clock synchronization block, a glitch generator, an impulses combiner, and a pulse shaping filter. It is designed and simulated in low-cost 0.18 μm UMC CMOS technology. The simulation results showed spectrum that covers whole UWB band and fully complies with the corresponding FCC spectral mask. The pulse duration is around 0.8 ns, and the peak-to-peak amplitude is 488 mV on 50 O output load. It has low power consumption of 1.1 mW corresponding to energy consumption of 11 pJ per pulse for 100 MHz pulse repetition frequency (PRF).

Comparison of Feedback Influence on Ring Oscillator Performance for IR-UWB Pulse Generator in 0.13 μm and 0.18 μm CMOS Technologies

A CMOS three-stage ring oscillator is examined in UMC 0.13 μm and 0.18 μm technologies. The influence of PMOS transistor and resistor, as inverter feedbacks, on the ring oscillator frequency and the peak-to-peak amplitude is investigated in both technologies. Furthermore, as the ring oscillator usually drives a buffer in pulse generator/transmitter chain, dependence of its Figures of Merit on the buffer feedback is presented in the paper. Simulation results showed that the ring oscillator frequency is strongly dependent on the inverter feedback. The presented techniques can be used to increase (resistive feedback) and control (PMOS transistor feedback) the ring oscillator frequency. As the ring oscillator is a part of an IR-UWB (Impulse Radio Ultra Wide Band) pulse generator, its oscillating frequency determines the spectrum central frequency and has significant effect on spectrum fitting within UWB FCC mask.