Microwave Engineering Europe - July/August 2008 - (Page 34)

34 PRODUCTS GaN HEMT transistors target 5-GHz WiMAX applications Cree, Inc is sampling two gallium nitride (GaN) HEMT transistors for use in WiMAX applications covering the 4.9 to 5.8-GHz frequency band. The transistors, designated CGH55015F and CGH55030F, claim to be the first released GaN HEMT WiMAX products specified to operate at up to 5.8 GHz. Significant potential benefits offered by the 15 W and 30 W devices include: Ñ a four-fold increase in efficiency compared with similar power level GaAs MESFET devices; Ñ elevated frequency operation compared with commercially available silicon LDMOS; Ñ operational capability in the license-exempt 5.8 GHz ISM (industrial, scientific and medical) band as well as 5.3 GHz and 5.47 GHz U-NII (Unlicensed National Information Infrastructure) bands; and Ñ superior linearity of better than 2.5 percent EVM at average power under a WiMAX signal at 25 percent drain efficiency covering an instantaneous bandwidth of 5.5 to 5.8 GHz. 60 GHz transceiver module ideal for short-range indoor communications Endwave Corporation has announced the release of a 60-GHz T/R module that targets short-range indoor communications that must transport data traffic at multigigabit speeds. The design allows full-duplex operation with flexible modulation and can also be operated in various radar modes, if desired. Typical specifications at 60 GHz are a receiver noise figure of 5 dB and a transmitter output power (at P1dB) of over +5 dBm with ±1.0 dB flatness over a 2-GHz operating bandwidth. Balance between I and Q ports measures better than 1.5 dB in amplitude and 10 degrees in phase over a 10 MHz (DC) to 1 GHz baseband frequency range. Measuring only 9 cm (3½ inches) in length, Both transistors are available with Òreference designÓ amplifier platforms. The CGH55015F and CGH55030F GaN transistors were developed to support the higher operational frequency and stringent efficiency and linearity requirements needed to enable next generation WiMAX base stations and access points. These 5 GHz transistors compliment the CGH35060 product that the company is releasing to round out their 3.5 GHz GaN HEMT WiMAX product line. This 60 W product is a direct result of customer feedback, and offers customers greater flexibility for 3.5 GHz WiMAX applications, particularly in Europe where remote radio heads (RRHs) are increasingly being used. www.mwee.com/208403040 the transceiver includes independent Tx and Rx local oscillators and versatile programmable phase lock loops. The reference frequency can be supplied externally at any of a number of different frequencies, including the popular 10 MHz standard. Units are available with built-in patch antenna arrays or with waveguide inputs and outputs. www.mwee.com/208403032 Application firmware for WiMAX MIMO transforms signal analyzers into MIMO analysis systems Rohde & Schwarz has added a suite of application Þrmware for WiMAX MIMO measurements in line with IEEE 802.16e-2005. Designated the FSQ-K94 option, it is designed to run on the companyÕs FSQ and FSG signal analyzers, and supports a combination of several analyzers for testing up to 4x4 MIMO systems. The FSQ-K94 application Þrmware can be used for testing semiconductor components such as WiMAX MIMO chipsets, ampliÞers and mixers, as well as complete products such as WiMAX base stations or pico stations. A large number of measurements required for testing MIMO systems can be performed by means of a single vector signal analyzer. To test the interaction between the individual components, however, two instruments may sometimes be required. In this case, the user can combine several FSQ or FSG analyzers to create a ßexible test solution made up of standalone signal analyzers for testing 4x4 MIMO systems, for example. Both the FSQ-K94 application Þrmware for WiMAX MIMO measurements and the FSQ-K93 application Þrmware for WiMAX SISO (single input single output) measurements, which has been on the market for some time, feature similar user interfaces and remote control commands. This reduces the time required for user training. Moreover, WiMAX MIMO measurements can easily be added to existing programs. Tried and tested FSQ-K93 functions such as automatic demodulation or user-speciÞc spectrum emission masks (SEM) are also provided in FSQ-K94. www.mwee.com/208800685 Spread-spectrum oscillator delivers XO stability while limiting EMI Vectron International has launched the VSS4 spreadspectrum oscillator that meets FCC restrictions on the amount of electromagnetic interference (EMI) allowed for a range of communications system and consumer electronics applications. The oscillator is said to provide the temperature and aging stability advantages of crystal oscillators along with the ability to signiÞcantly reduce the amount of oscillator-produced EMI. It enables design engineers to meet performance requirements and the FCCÕs EMI regulations for a host of consumer and enterprise applications including wireless, DSL, and broadband. The VSS4 offers a frequency range from 12 MHz to 168 MHz, operates off 3.3-V and features an enable/ disable feature to allow the clock output to be disabled for board testing. www.mwee.com/208800712 Microwave Engineering Europe ● July/August 2008 ● www.mwee.com http://www.mwee.com/208403032 http://www.mwee.com/208403040 http://www.mwee.com/208800712 http://www.mwee.com/208800685 http://www.mwee.com

Table of Contents Feed for the Digital Edition of Microwave Engineering Europe - July/August 2008

Microwave Engineering Europe - July/August 2008 Contents News Comment Cover Feature: Effective EM Simulations with Micro−λ Resolution in Macro-λ Objects — General Huygens Box Implementation RF CMOS: Programmable Transceiver IC Minimises OEM Inventory for Femtocells CAD/EDA: Software-Defined Radio Platforms CAD/EDA: Cadence Enhances RF Verification While AWR Delivers an Improved Microwave Office How to Meet the Design Challenges of WiMAX Power Amplifiers Products Calendar

Microwave Engineering Europe - July/August 2008

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