TLM time-domain modelling and the use of windowing profiles for frequency-domain transformations applied to microwave cavity resonators

This paper presents developments made to the TLM method in the time to frequency-domain transformation of the impulse response solution. An improvement to the technique by which the three-dimensional TLM time-domain method is post-processed is presented. It is shown that the selective choice of a particular data windowing profile plays a significant role in the accuracy of the results, clarity of output response and the extraction of the S-parameters

A new HEMT breakdown model incorporating gate and thermal effects

This paper presents a comprehensive physical model for the breakdown process in HEMTs. The model is integrated into in a fast quasi-two-dimensional HEMT physical simulator. The work is based on a full study of the complex interactions between the different breakdown mechanisms and the influence of design parameters. The model takes account of tunnelling effects in the region of the gate metallization, and of the thermal effects in the active channel under the gate region

A new HEMT breakdown model incorporating gate and thermal effects

This paper presents a comprehensive physical model for the breakdown process in HEMTs. The model is integrated into in a fast quasi-two-dimensional HEMT physical simulator. The work is based on a full study of the complex interactions between the different breakdown mechanisms and the influence of design parameters. The model takes account of tunnelling effects in the region of the gate metallization, and of the thermal effects in the active channel under the gate region

Meeting the Needs of Cellular Dual-Mode (EGPRS/3G) Power Amplifiers with a Unique J-PHEMT Process and Novel Control Architecture

Based upon a unique Junction-PHEMT device, a novel method of providing high efficiency PA power control for variable envelope modulation schemes is demonstrated for EDGE and WCDMA. The method of control allows for substantially higher efficiency levels under typical handset operating conditions than those of conventional linear power amplifiers, on a par with polar loop solutions, whilst avoiding the necessity for complex control loops. An immediate benefit of the approach includes the ability to add EDGE front-end capability to a GSM handset without incurring a significant size or component cost impact. Furthermore, the method of control aids the future prospect of single transmit strip multi-mode configurations (GSM/EDGE/WCDMA) in order to achieve considerable size and cost advantages