High Power Disk Combiners For DCS1800/UMTS

Power Combining For Cellular Base Stations

As the linearity requirements on systems increase and the avaiable spectrum decreases a need for devices that can combine many communication channels emerges. This is currently achieved using conventional copper cavities. These have the disadvantages of being large and bulky, and also of being lossy. The use of HTS materials enables a multi-carrier combiner to be impelemnted from 50mm diameter wafers. The devices exhibit less than 0.4dB insertion loss at the operational frequency of 1.8GHz 



Simulations for the disk structure show the peak current density is low at the edges of the structure. This is in contrast to linear type 1D structures where we have a current maximum at the edges (can be as much as an order of magnetude higher than at the center). This has implications for the power handling capabilities. 


Network Analyser Measurements



  • TM011 Mode at 1.74GHz
  • Insertion loss 0.3-0.4dB (including connectors)
  • 40MHz 3dB bandwidth
  • Tempaerature 60K Spectral Re-growth Measurements