1. Measurement of Efficiency for power combiner

2. May 99Through property for 6*4 array power combiner2 Circuit Topology Use 50 Ohms transmision line to replace the MMICs Waveguide environment Slotline-to-microstrip transition From 2 trays to 6 trays, different schemes are tested. ( The 6 metal cards are always mounted, but circuit tray number varies.)

3. May 99Through property for 6*4 array power combiner3 Impedance of bond wire Bond wire Total A, B, C, D 4 connection for each path For each connection, 6*0.001” gold wire From 1 -> 1, 1.4 Ohm From 3 -> 3, 0.8 Ohm From 5 -> 5, 1.4 Ohm From Gnd -> Gnd, 0.2 Ohm 1 3 3 5 5 1 D CB A Gnd

4. May 99Through property for 6*4 array power combiner4 S11 < - 11 dB S21 vary from - 1.1 dB to - 1.5 dB S parameters: S parameters of 2-Trays combiner Low insertion loss Low return loss The best among all Comparison :

5. May 99Through property for 6*4 array power combiner5 S11 < - 8 dB S21 vary from - 1.3 dB to - 2.4dB S parameters: S parameters of 6-Trays combiner Low insertion loss, but higher than 2 and 4 trays Return loss is higher than 2 and 4 trays too Comparison :

6. May 99Through property for 6*4 array power combiner6 Over-sided 8-Trays combiner 8-Tray power-combiner is tested To hold more circuit trays, an over-sided wave- guide is used The taper wave-guide has showed low reflection, and could match well with WR-94 wave-guide Oversized taper Wave-guide Oversized taper Wave-guide WR-94 Wave-guide WR-94 Wave-guide 8-Tray Power-Combiner

7. May 99Through property for 6*4 array power combiner7 Waveguide Taper Structure Linear Taper Transition Oversized Waveguide Opening (1.12 in. x 0.9 in.) 4 in. Transition Each Side Oversized Waveguide Environment to Accommodate the 8-Tray System Oversized Opening Standard Opening

8. May 99Through property for 6*4 array power combiner8 S11 < - 7.6 dB S21 vary from - 1.1 dB to - 2.5 dB S parameters: S parameters of 8-Trays combiner Insertion loss is higher Comparison :

9. May 99Through property for 6*4 array power combiner9 How the loss is calculated? The loss is evaluated by the ratio of the output power over the power which could be transmitted forward. Power Combiner No incident wave at Port2 (Radiation & conduction loss)

10. May 99Through property for 6*4 array power combiner10 How the efficiency is calculated? Li = Lo, and is half of the total loss ( in dB). The Efficiency is calculated on one side antenna array, and is Li or Lo on percent. N-way Combiner System

11. May 99Through property for 6*4 array power combiner11 Loss of 2-Trays combiner S21 has ripples due to reflection of antenna S parameters: Loss is lower than S21 Insertion loss is almost constant over all frequency Average loss is –1.30 dB Average Efficiency is 86.1% Loss :

12. May 99Through property for 6*4 array power combiner12 S21 is lower than 2-trays S parameters: Loss of 6-Trays combiner Loss is more than 2-Trays Average loss is –1.30 dB Average Efficiency is 86.1% Loss :

13. May 99Through property for 6*4 array power combiner13 Loss of 8-Trays combiner S21 has ripples due to reflection of antenna S parameters: Average loss is –1.34 dB Average Efficiency is 85.7% Loss :

14. May 99Through property for 6*4 array power combiner14 Summary The power combiner’s efficiency keeps at constant around 86% when the active device increase from 8 to 32 pieces.