Fully Automated Laser-Adjustable Compact Microwave Transceivers with Integrated Local Oscillator

Based on fully automated laser-trimming technology for RF-modules, a family of compact and cost effective microwave transceivers have been developed. A local microwave oscillator is integrated in the transceiver, in order to achieve a highly integrated microwave sub-unit. They are realised for the 18, 23, 26 and 28GHz frequency bands with modulation schemes up to 128QAM and intended for outdoor applications. To compensate for material, components and manufacturing tolerances fully automated active laser-trimming procedures are used during the production process to adjust several essential parameters like TX-gain, oscillator frequency or centre frequency of a narrow band-pass filter. In addition, by using laser trimming technology different versions of the transceiver can be handled with great flexibility. The transceivers offer high TX output power with an excellent intermodulation characteristic. This is achieved by adaptive pre-distortion. In addition, the radios have a low RX noise figure