| 1. |
- Abbasi, Morteza, 1982, et al.
(author)
-
A broadband differential cascode power amplifier in 45 nm CMOS for high-speed 60 GHz system-on-chip
- 2010
-
In: 2010 IEEE Radio Frequency Integrated Circuits Symposium, RFIC 2010; Anaheim, CA; 23 May 2010 through 25 May 2010. - 1529-2517. ; , s. 978-142446242-1-
-
Conference paper (peer-reviewed)abstract
- A compact two-stage differential cascode power amplifier is designed and fabricated in 45 nm standard LP CMOS. The cascode configuration, with the common gate device placed in a separate P-well, provides reliable operating condition for the devices. The amplifier shows 20 dB small-signal gain centered at 60 GHz with a flat frequency response and 1-dB bandwidth of 10 GHz. The broadband large-signal operation is also ensured by providing constant load resistance to both stages over the entire band and coupling them with a dual resonance matching network. The chip delivers 11.2 dBm output power at 1-dB compression and up to 14.5 dBm power in saturation. The power amplifier operates with 2 V supply and draws 90 mA total current which results in 14.4% maximum PAE. The output third order intercept point is measured to be 18 dBm for two-tone measurement at 60 GHz with 0.5 GHz, 1 GHz and 2 GHz frequency separations. © 2010 IEEE.
|
|
| 2. |
- Abbasi, Morteza, 1982, et al.
(author)
-
A direct conversion quadrature transmitter with digital interface in 45 nm CMOS for high-speed 60 GHz communications
- 2011
-
In: Digest of Papers - IEEE Radio Frequency Integrated Circuits Symposium. Baltimore, 5-7 June 2011. - 1529-2517. - 9781424482931
-
Conference paper (peer-reviewed)abstract
- A compact 60 GHz direct conversion quadrature transmitter is designed and fabricated in 45 nm standard LP CMOS. The transmitter features an integrated power amplifier with continuous output level control and interfaces binary data signals with nominal peak-to-peak voltage swing of 300 mV. The highest measured modulation bandwidth is limited by the measurement setup to 4 GHz but is simulated to be as high as 10 GHz. In single sideband up-converting operation mode, the measured image suppression ratio is 22 dB with 36 dB of carrier suppression corresponding to approximately 8% EVM in the output signal constellation. The output RF frequency can be from 54 GHz to 66 GHz to accommodate several channels and the output power can be adjusted from -3 dBm to 10 dBm. The chip is operated from a 2 V supply and draws 180 mA current.
|
|
| 3. |
- Abbasi, Morteza, 1982, et al.
(author)
-
Direct carrier quadrature modulator and Demodulator MMICs for 60 GHz gigabit wireless communications
- 2011
-
In: Asia-Pacific Microwave Conference Proceedings (APMC 2011; Melbourne, VIC; 5 - 8 December 2011). - 9780858259744 ; , s. 1134-1137
-
Conference paper (other academic/artistic)abstract
- A 60 GHz direct carrier quadrature modulator is designed and fabricated in 0.15 μm mHEMT technology. The design is based on passive mixers and therefore reciprocal which makes it possible to be used both as modulator and demodulator. The modulator has an input bandwidth of 0-5 GHz on each of the I and Q ports and an RF bandwidth of 53-68 GHz. Carrier leakage to the output port is eliminated by addition of an inductive path from the LO port to the RF port. The modulator requires 5 dBm LO power and can output up to -6 dBm RF power in linear region and up to -4 dBm when driven into saturation. When operated as an SSB mixer, the conversion loss is measured to be 11 dB and image and LO signals are suppressed by as much as 30 dB compared to the desired signal. For demonstration, a pair of the presented modulator/demodulator is used to transmit 7Gbps BPSK signal over 1m and 10Gbps QPSK signal over 0.5m wireless link.
|
|
| 4. |
- Hallin, Joakim, 1965, et al.
(author)
-
A 100-Gb/s 1:4 Demultiplexer in InP DHBT Technology
- 2006
-
In: IEEE Compound Semiconductor Integrated Circuit Symposium, Technical Digest 2006, 12-15 November 2006, San Antonio, TX, USA. - 1424401267 ; , s. 227-230
-
Conference paper (peer-reviewed)
|
|
| 5. |
|
|
| 6. |
- Hallin, Joakim, 1965, et al.
(author)
-
A 165-Gb/s 4:1 Multiplexer in InP DHBT Technology
- 2006
-
In: IEEE Journal of Solid-State Circuits. - 0018-9200. ; 41:10, s. 2209-2214
-
Journal article (peer-reviewed)abstract
- This paper presents a 4:1 multiplexer fabricated in InP double heterojunction bipolar transistor (DHBT) technology. The multiplexer works up to 165 Gb/s at a supply voltage of -3.2 V consuming 1.6 W. It is a half-rate multiplexer using a multi-phase clock architecture. The main design challenge was to ensure correct timing between clock and data signals. © 2006 IEEE.
|
|
| 7. |
|
|
| 8. |
|
|
| 9. |
- Kjellberg, Torgil, 1962, et al.
(author)
-
A Compact Cascode Power Amplifier in 45-nm CMOS for 60-GHz Wireless Systems
- 2009
-
In: 2009 ANNUAL IEEE COMPOUND SEMICONDUCTOR INTEGRATED CIRCUIT SYMPOSIUM - 2009 IEEE CSIC SYMPOSIUM, TECHNICAL DIGEST 2009. - 1550-8781. - 9781424452606 ; , s. 95-98
-
Conference paper (peer-reviewed)abstract
- This paper presents a power amplifier in 45nm CMOS technology operating in the 50 to 60-GHz frequency range. It uses a single-ended topology with two cascode stages. A gain of 19.6 dB is obtained at 54 GHz where the gain peaks, and 17 dB at 60 GHz. The measured output-referred 1-dB compression point is 8.7 dBm at 60 GHz and a supply voltage of 2.1 V, and the saturated output power is 13.5 dBm. The bias conditions are shown to be reliable through lifetime measurements. The active chip-area measures 160 mu m x 110 mu m.
|
|
| 10. |
- Kjellberg, Torgil, 1962
(author)
-
Semiconductor Lasers with Gratings Defined by Electron Beam Lithography
- 1993
-
Doctoral thesis (other academic/artistic)abstract
- This thesis deals with the fabrication and characterization of semiconductor lasers with gratings defined by electron-beam lithography (EBL). Both distributed-feedback (DFB) lasers for fiber-optic communication and grating-surface-emitting (GSE) lasers suitable for a number of novel applications, from free-space communication to optical processing, are treated. In the first part of the thesis, the technical limitations of EBL for grating fabrication in general and DFB grating fabrication in particular as well as its possibility to enhance the performance of DFB lasers by advanced grating designs are studied. Small-area, high- resolution EBL patterning is associated with field-stitching errors. The statistical nature of these errors and their effect on the single-mode (SM) stability of DFB lasers have been investigated. It is shown that the field-stitching accuracy is sufficient to produce high-quality gratings for DFB lasers if certain precautions are taken considering exposure conditions and laser design. A study of the spectral characteristics of DFB lasers with different grating configurations has also been carried out. It was found that good AR-coating of the cleaved facets and very accurate processing control is necessary in order to benefit from the l/4-shifted and multiple-phase-shifted (MPS) DFB laser structures as compared to regular unshifted DFB lasers. The MPS structure was shown to be effective to enhance the SM performance of DFB lasers with strong coupling and to obtain narrow linewidths. Finally, a new technique for the realization of a nonuniform coupling coefficient in DFB lasers is demonstrated. It enables a large variation and precise control of the coupling strength. The second part of the thesis presents GSE lasers with record low threshold current densities (below 100 A/cm2) and an improved lateral mode control in broad devices. The low threshold current densities were the result of high-reflectivity and low-absorption gratings in conjunction with lateral index guiding and current confinement in the gain section. The devices contained a strained-layer InGaAs/BlGaAs single-quantum-well and a thin etch-stop layer to allow precise control of the grating position relative to the active layer. Uniform and well-defined rectangular surface- gratings were fabricated using EBL and chemically-assisted ion-beam etching. A study of the dependence of the threshold current and power-current linearity on the detuning of the Bragg wavelength from the gain peak is also presented. A strong dependence of the linearity on the detuning was found and the lasers showed good linearity at the wavelength yielding the lowest threshold current. Finally, GSE lasers with integrated dry-etched corner reflectors were fabricated. Well behaved lateral modes were observed in 70 µm wide lasers, emitting beams with a low divergence in both the lateral and longitudinal directions at low current injection.
|
|
