Inhyo Ryu

A 3–10 GHz flexible CMOS LO generator for MB-OFDM UWB application using wide tunable VCOs

A frequency synthesizer for MB-OFDM UWB system is implemented in CMOS RF process. The LO generator includes three wide tunable VCOs, PLLs, and quadrature generators. This synthesizer with three VCOs gives more flexible power management scheme and generates lower spurious tones than single side-band mixing method. This scheme supports all band groups except band group 2 which wireless LAN application occupies. Local oscillator including PLLs consumes 17.8 ~ 45.7 mA according to TFC code from 1.2 V power supply. Phase noise has been measured less than -100 dBc/Hz over the operating frequency range.

Design and Analysis of an Ultra-Wideband Automatic Self-Calibrating Upconverter in 65-nm CMOS

In this paper, an ultra-wideband (UWB) upconverter is proposed that has automatic self-calibrating circuits for the in-phase/quadrature mismatch correction and the local (LO) leakage suppression. The proposed self-calibrating circuits have been devised to have UWB functionality without help of the baseband processor. In addition, calibrating circuits do not need any additional analog-to-digital converter or sample-and-hold capacitors that are used to store and update the minimum power because the proposed calibrators find the solution from informations in current state. To verify the performance, the upconverter was applied to an UWB transmitter (Tx), operating from 3.1 to 4.8 GHz and from 6.3 to 9 GHz in 65-nm CMOS. The measured data shows UWB performance for the sideband rejection up to 9 GHz and the LO leakage suppression up to 5 GHz, respectively. The automatically calibrated Tx has error vector magnitude of lower than -20 dB, output 1-dB compression point of -6 dBm, LO leakage of lower than -43 dBm, and sideband suppression ratio of higher than 45 dBc with current consumption of 175 mA from a 1.2-V power supply for all supporting bands and time frequency codes defined in WiMedia UWB specifications.

An Ultra-wideband transmitter with automatic self-calibration of sideband rejection up to 9 GHz in 65nm CMOS

An Ultra-wideband (UWB) transmitter is proposed that can correct phase errors in quadrature local (LO) signals automatically without help of baseband processor (BBP), operating from 3 to 9 GHz in 65 nm CMOS. The measured tuning range for sideband rejection is 32.7 dB at 7.7 GHz and 13.6 dB at 8.7 GHz. The measured EVM is lower than −20 dB for all supporting bands and TFCs (Time frequency codes) that are prescribed by WiMedia alliance. The power consumption of the transmitter including LO path and PLLs is 210 mW from a 1.2 V supply.

A 65nm CMOS low-noise three band group WiMedia UWB receiver

A low-noise and high-gain ultra wideband (UWB) receiver was developed using a 65nm CMOS technology and a wafer-level fabricated package. In order to enhance the gain and noise figure over a wide frequency band, the resistive feedback amplifier and two cascode stages with the inductive load resonating at three different frequencies are employed. The fabricated UWB receiver showed a high gain of 72.6 dB ± 0.7 dB overall operating frequency range, and an average noise figure of 4.1 dB in 3168 to 4752 MHz, 4.3 dB in 6366 to 7920 MHz and 5.1 dB in 7392 to 8976 MHz frequency band, respectively. The noise figure at high frequency edge is lower than 6 dB. The measured sensitivities in three band groups meet all WiMedia PHY specifications.

A WiMedia UWB transmitter up to 9GHz in 65nm CMOS and Wafer-Level Fabricated Package

A 3.1–4.7GHz and 6.3–9GHz RF transmitter fabricated in a 65nm CMOS technology and packaged with a Wafer-level Fabricated Package (WFP) is presented. For high frequency and wideband performances, all the effects of package are considered and loopback paths with a power detector are implemented. A new structure of T/R switch is devised for the low noise performance of Rx and the high linearity of Tx. With these circuits, the transmitter features high linearity, low power consumption and small chip area meeting all the WiMedia PHY spec.