Jeong-seok Lee

Resonant Regulating Rectifiers (3R) Operating for 6.78 MHz Resonant Wireless Power Transfer (RWPT)

The design of a Resonant Regulating Rectifier (3R) capable of switching-mode operation is presented. The proposed 3R is a highly efficient receiver circuit intended for use in Resonant Wireless Power Transfer (RWPT) application with a 6.78 MHz resonant frequency. Owing to the inductance of resonant coils, the 3R does not require any additional inductor for the switching-mode regulation. The transmitted power via the RWPT with the 3R ranges from 0 W to 6 W, and its peak efficiency reaches 86%. It employs the Continuous Conduction Mode (CCM) and Discontinuous Conduction Mode (DCM) for different output power levels. This helps to increase the output power and to lower the voltage stress on the transistor. Fabricated in 0.35 μm BCD technology, the 3R circuit occupies an area of 2.35×2.35 mm2. The functionality of the 3R is successfully demonstrated using a transmitter circuit with resonant coils.

Colorless Operation of WDM-PON Employing Uncooled Spectrum-Sliced Reflective Semiconductor Optical Amplifiers

We demonstrate a low-cost wavelength-division-multiplexed passive optical network based on colorless uncooled spectrum-sliced reflective semiconductor optical amplifiers. In this network, we achieve bit-error rates of better than 10-10 over 32 100-GHz-spaced channels from 0 degC to 60 degC in 155-Mb/s transmissions. The penalties due to dispersion effect and Rayleigh backscattering interference over 25 km are almost negligible. We also present colorless operations over 16-channel coverage in outdoor temperature range

A gain-clamped SOA with distributed Bragg reflectors fabricated under both ends of active waveguide with different lengths

We demonstrate a gain-clamped semiconductor optical amplifier (GC-SOA) which has gratings under both end regions of an active waveguide. Two gratings of the new GC-SOA are fabricated in different lengths. Their lasing modes and gain characteristics are measured and analyzed with different combinations of grating lengths. It shows different gain and noise characteristics according to the measurement direction in asymmetric grating combinations.

A Novel Hybrid WDM/SCM-PON using Reflective Semiconductor Optical Amplifier

A hybrid wavelength-division-multiplexed/sub-carrier-multiplexed passive optical network having the same wavelength both upstream and downstream is presented by using a reflective semiconductor optical amplifiers (RSOA) as a modulator. We investigated the down stream of 622.08Mbps using a DFB-LD with direct modulation and the 100Mbps upstream using a RSOA as a modulator with 900MHz SCM signal. In our scheme, a novel efficient and cost effective WDM/SCM-PON using same wavelength for down/up stream at each ONU proposed and demonstrated by BER measurements.

23Gbps 9.4pJ/bit 80/100GHz band CMOS transceiver with on-board antenna for short-range communication

Fully integrated 80GHz-band and 100GHz-band transceiver ICs using 65nm CMOS technology and on-board antennas for high-speed/short-range wireless communication system are demonstrated. To realize higher speed and lower power consumption than those of a 60GHz-band standard application such as IEEE802.11ad, a simple transceiver architecture with non-coherent amplitude shift keying (ASK) modulation method using W-band (75-110GHz) is adopted. The aggregate 80/100GHz-band transceiver modules demonstrate 23Gbps over 10mm wirelessly with power consumption of 216mW. The developed transceiver modules achieve the highest speed of wireless communications above 60GHz-band and show a potential for future applications of 100Gbps high-speed short-range communications.

A low-power 71GHz-band CMOS transceiver module with on-board antenna for multi-Gbps wireless interconnect

Fully integrated millimeter-wave transceiver ICs using 65nm CMOS technology and on-board antenna for highspeed/short-range wireless communication system are described. To realize high-speed and low power consumption for a mobile application, a simple transceiver architecture with non-coherent amplitude shift keying (ASK) modulation method is adopted. The transceiver ICs are flip-chip bonded on boards and connected with on-board antenna for a simple and low cost transceiver system. The developed transceiver system module demonstrates 5Gbps/3.8Gbps at wireless communication range of 5mm/10mm and power consumption of 79.6mW with a carrier frequency of 71GHz. To our best knowledge, this is the first report of a millimeter-wave, above 60GHz, CMOS transceiver module with on-board antenna for a highspeed/short-range wireless communication system.

An optical amplifier for metro WDM networks, based on a gain-clamped semiconductor optical amplifier

An optical amplifier for metro WDM networks, based on a gain-clamped semiconductor optical amplifier is proposed. The amplifier (RAGCSOA) consists of a low gain Raman fiber amplifier and a gain-clamped semiconductor optical amplifier. The RAGCSOA has over 20 dB gain and a noise figure below 3 dB. In addition, the potentially compact amplifier shows negligible transients under dynamic add-drops. Sixteen channels of 10 Gb/s signals were successfully transmitted over five NZDSF spans of 80 km using RAGCSOAs. RAGCSOAs were also used to successfully transmit sixteen channels of 10 Gb/s WDM signals over four 40km spans of SMF with add-drops. No penalty was observed when 15 out of 16 channels were dynamically add/dropped in all the transmission systems. The RAGCSOA can be very compact when a GCSOA chip and a Raman pump LD chip are packaged in a module.