The development of X-band klystrons at SLAC originated with the idea of building an X-band Linear Collider in the late 1980’s. Since then much effort has been expended in developing a reliable X-band Power source capable of delivering >50 MW RF power in pulse widths >1.5 μs. I will report on some of the technical issues and design strategies which have led to the current SLAC klystron designs.

A new out-of-band power suppression method for SC-OFDM is proposed in this paper. In the proposed method, phase continuity between SC-OFDM blocks is preserved by inserting one static “anchor symbol”. As a result, out-of-band power emissions are reduced without BER performance degradation. Both simulation and experimental results indicate that reduction of out-of-band emissions up to 13dB can be...

Challenges:  Algorithm Development  Non-ideal in-band filtering and strong adjacent-band primary users introduce in-band interfering power  Increases estimation error  Increases probability of false-alarm  Decreases probability of false-alarm  Chip Implementation  Wideband sensing chip requires high sampling rate  Power efficiency issue  Large dynamic range signal requires large WL  A...

Cognitive Radio (CR), which aims to improve spectrum utilization by accessing the spectrum originally licensed to a primary system, is a promising concept. In cognitive radio system based on orthogonal frequency division multiplexing (OFDM), the optimized algorithms for sub-carrier power allocation share the problems of complex iterative calculation and difficult realization. In this case, a su...

This thesis describes the design of a low-power speech detector chip. It will be used between an electret microphone and a microcontroller and will generate a digital wake-up signal for the microcontroller when the audio signal is sufficiently “speechlike” to initiate higher-level processing of the amplified audio signal. The rest of the time, the microcontroller will sleep and consume nearly n...

A digital look-up table adaptive predistortion technique using a six-port receiver for power amplifier linearization is presented. The system is designed in Ka-band for a DVB-S2 satellite link. We use a six-port receiver at the linearizationloop in place of classic heterodyne receivers. The six-port receiver is implemented by the use of passive microwavecircuits and detector diodes. This approa...

According to theoretical accounts, both, N-back and complex span tasks mainly require working memory (WM) processing. In contrast, simple span tasks conceptually mainly require WM storage. Thus, conceptually, an N-back task and a complex span task share more commonalities as compared to a simple span task. In the current study, we compared an N-back task, a complex operation span task (Ospan), ...

The aim of this study was to clarify the relationship between EEG power and neuroticism trait. We used correlational method in order to examine the hypotheses. The participants included twenty-five undergraduate students (age mean= 21.36, SD= 23.39) at Ferdowsi university of Mashhad that were selected as volunteers. All participants were right-handed and had normal or corrected-to-normal visual...

Integration of multi-mode multi-band transceivers on a single chip will enable low-cost millimeter-wave systems for next-generation automotive radar sensors. The first dual-band millimeter-wave transceiver operating in the 22–29-GHz and 77–81-GHz short-range automotive radar bands is designed and implemented in 0.18m SiGe BiCMOS technology with of 200/180 GHz. The transceiver chip includes a du...