Significant progress in modeling and manufacturing technologies open wide possibilities for performance improvements of millimeter-wave vacuum electron devices. However, many practical aspects should be considered to realize reliable long-life high-power sources. These are: thermal and RF stability, materials and assembly sensitivity to manufacturing, electrical stresses, cathode poisoning prevention, thermal beam effects, and many others. We address the full spectrum of design and manufacturing aspects while developing state-of-the-art extended interaction klystrons (EIKs). EIKs provide unprecedented RF performance and reliability in a compact user-friendly package. This paper discusses EIK design methodology and manufacturing concepts stating self-imposed restrictions and design modifications enhancing power capability, bandwidth, and extending operating frequencies into the terahertz region.

A CW 48 GHz 500 Watt saturated 250 MHz Extended Interaction Klystron (EIK) has been developed and delivered for use in the ESA Alphasat program. Designed for integration into a new CPI Satcom Division High Power Amplifier (HPA), this EIK may be operated in a linear mode up to 300 Watts rated output power, with performance optimized at 75 Watts. The EIK is temperature stabilized over a 60°C temperature range such that no field adjustment is required. This paper summarizes design parameters and test results.

A novel model of the compact high power 264 GHz CW Extended Interaction Oscillator has been developed by CPI Canada. By combination of mechanical tuning and electronic switching between two operating modes, this EIO provides over 1 W of power in the range of 258 to 270 GHz. Liquid cooling is used to stabilize RF circuit temperature and prevent frequency detuning. Further development is ongoing to support THz operation with enhanced output power, which is currently limited by vacuum window capability.

A new model of vacuum tube amplifier, designed to produce over 10 Watts at 263 GHz is in development at CPI Canada. This device uses CPI's Extended Interaction Klystron technology, which has previously demonstrated good results from 17 to 220 GHz. With recent completion of a 264 GHz CW tunable oscillator, the amplifier development will extend the demonstrated envelope for EIKs to a frequency and power useful in DNP and other mm-wave applications.

CPI Canada have produced EIKs and EIOs at frequencies up to 220 GHz. Recent development programs have demonstrated that the technology exists to design and build Extended Interaction devices at low THz frequencies. This paper describes current and predicted performance of these devices, the design challenges and solutions to enable this performance.

The design and test of an Extended Interaction Klystron operating at 17.2 GHz is presented. The program goal is to demonstrate the feasibility of meeting the technical requirements of the proposed CoReH20 mission. The device will provide over 3.5kW of peak RF power and 20% duty cycle in a conduction cooled configuration weighing less than 9 kg.

The development of new terahertz power amplifiers at 0.67, 0.85 and 1.03 THz presents significant challenges in both design and fabrication. This paper describes the design challenges and methodology, an outline design of the new device and an analysis of fabrication techniques considered.

This paper reviews the technology and demonstrated capability of millimeter wave Extended Interaction Klystrons for use in wide range of radar systems. It discusses design and manufacturing concepts stating selfimposed restrictions and design modifications to enhance RF performance, lifetime, reliability and extended operating frequency into the THz region. Presented data are supported using information provided by various academic and industrial customers.

This paper describes the dispenser cathode technology and cathode life testing at high current density that together underpin the design of a W-band 2kW Extended Interaction Klystron developed for the nadir-pointing 94Ghz radar of the CloudSat Earth Observation satellite. The cathode operates at an emission current density of 11.3 Amps/cm(2) and, prior to launch, a 99% confidence level of meeting the mission goal of 22,500 hours operating life in orbit was required. The measured performance of the EIK amplifier in orbit is reported together with examples of cloud profiles obtained by the radar. The EIK life model has been validated and, based on the flawless performance of the radar in orbit and the high data yield, the mission has been extended from 2 years to 5.

EarthCARE (Earth Clouds, Aerosols and Radiation Explorer) is the 6th Earth Explorer Core Mission of the European Space Agency and a joint undertaking with the Japan Aerospace Exploration Agency (JAXA). It will study and analyze the interaction and impact of clouds and aerosols on the Earth's radiative budget. Along with other instruments, the satellite payload will include a 94 GHz Cloud Profiling Radar (CPR) with Doppler capability. This paper presents the development of a High Power Amplifier for the EarthCARE CPR and reviews HPA requirements, design and performance.

This paper reviews the technology and demonstrated capability of mmW and Sub-mmW Extended Interaction Klystrons at CPI Canada. It discusses design and manufacturing concepts stating self-imposed restrictions and design modifications enhancing power capability, bandwidth and extending operating frequency into the THz region.

This presentation describes the performance of a recently developed 218 GHz extended interaction klystron (EIK) amplifier producing 7W CW and weighing less than 4.3 kg.

The EIKs described have demonstrated capability to provide mmW power suitable for improved ESR and NMR systems. The performance of EIKs at 94 GHz and 220 GHz is reviewed and possibilities for future improvement in performance, including increasing frequency, will be discussed. Presented data are supported by information provided by various academic and industrial customers.

In this paper, CPI Canada enhancement of the capabilities of the Ka-band extended interaction klystrons (EIK) for the Satcom Communication Uplink community is discussed.

This paper presents on-orbit performance of the CloudSat extended interaction klystron (EIK) and reviews requirements, design and performance of EIK's for future space missions. The CloudSat mission provides cross-sectional view of clouds with information on their thickness, altitude, optical properties, water and ice content. It is concluded that following successful development and on-orbit operation of the CloudSat EIK, more flight models of W-band and Ka-band EIK's are currently under development.

This paper details the development and test of a 2.2% bandwidth, 95 GHz Extended Interaction Klystron (EIK). This bandwidth was achieved with a peak RF power of ~1 kW (100 W average) while maintaining a compact size and weight (less than 6 kg).

This paper reviews the technology and demonstrated capability of mmW and Sub-mmW Extended Interaction Klystrons at CPI Canada. It discusses design and manufacturing concepts stating self-imposed restrictions and design modifications enhancing power capability, bandwidth and extending operating frequency into the THz region.

This presentation describes the design and test results of a 1.6 kW peak, 400 W average power amplifier utilizing an Extended Interaction Klystron (EIK) operating at 95 GHz. The EIK and power supply form a suitcase-sized package with an overall electrical efficiency greater than 20%. Also presented will be the design of a 95 GHz EIK amplifier with a target output power level of 1 kW CW.

This paper reviews the demonstrated capability of mmW and Sub-mmW extended interaction klystrons at CPI Canada. It discusses design and manufacturing concepts including self-imposed restrictions followed by performance expectations into the THz region.

CPI Canada is developing a new-line of pulsed Ka-band amplifiers, featuring ultra-compact size, higher power, improved efficiency, conduction cooling and space-grade reliability. The major goal of the development is to address the needs of several current and future space missions. Space-borne Ka-band radars are proposed for precision measurements of global precipitation, water surface elevation and for high resolution mapping of planetary images. This abstract presents highlights of many technological innovations used for extended interaction klystron (EIK) design, and summary of the space development programs, which are underway at CPI Canada