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New 283-365 GHz integrated YIG multiplied local oscillator with full electronic tuning

A new 283-365 GHz integrated multiplied YIG local oscillator with full electronic tuning has been developed at IRAM. The chain includes commercially available devices together with specific band pass filters, couplers, and harmonic mixers, designed in-house (Figs. 7,8).

Figure 7: Picture of the 283-365 GHz integrated YIG LO
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Figure 8: 283-365 GHz integrated YIG LO diagram
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The LO output power is between 100 and $200 \mu $W over the band. The band-pass and high-pass filters included in the new LO chain reduce the harmonic products that fall in the DSB SIS mixer RF bandwidth, and there is no significant noise temperature excess compared with a traditional mechanically tuned Gunn multiplied LO and compared with a NRAO YIG LO when the IRAM YIG LO is used to pump a DSB SIS mixer (Fig. 9). The LO was locked with a 1.875 GHz reference over the full band.

Figure 9: Comparison between the DSB SIS mixer noise temperature when it is pumped with a multiplied mechanically tuned Gunn, and when it is pumped with a full electronically tuned NRAO or IRAM YIG LO
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Francois MATTIOCCO


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Next: Scientific Results in Press Up: IRAM Newsletter 64 (December 2005) Previous: Cloudsat Status