PCB: Phase Shifters and Amplifiers
Objective
To ensure each PCB containing a phase shifter and an amplifiers work together to accomplish a phase shift ranging from at least 0 to 180 degrees.
Proof of Concept
Input a DC voltage into the amplifier and the output voltage of the amplifier will be the input voltage of the phase shifter. Input a 15 V control voltage into the amplifier, this will be the bias pin of the phase shifter. Measuring the output of the amplifier with a multimeter and the output of the phase shifter with a mini-Vector Network Analyzer (VNA). Graph the measured phase shift versus the bias voltage in order to match the graph above.
Pass criteria: Minimum Phase shift range of at least 0º to 180º or above 180º
Fail criteria: Phase shift range of anything not within 0º to 180º or above 180º
Methods
Need to ensure that the phase shifter can still perform a phase shift ranging from 0 to 180 degrees in the 915 MHz ISM frequency band for a range of bias pin voltage values provided by the output of the amplifier and ranging from 0 to 15 V. We performed this test by supplying the phase shifter with a bias pin voltage ranging from 0 V to 15 V in steps of 0.1 V. The amplifier was supplied with a 15 V power, and the input voltage going into the amplifier ranged from 0 to 5 V in steps of 0.1 V such that the output of the amplifier ranged from 0 to 15 V in steps of 0.5 V. Therefore, the output of the amplifier supplied the voltage to the bias pin of the phase shifter. In order to observe which frequency resulted in the largest phase shift range, we tested each PCB at the following frequencies: 917 MHz, 920 MHz, 925 MHz, and 928 MHz. Once all the phase shifters were tested, we set our reference phase shifter to be the one with the greatest phase shift range.
Results
Our ideal phase shift for the phase shifter and amplifier test would be from 0º to 180º or higher than 180º when having a gain of 5V/V for the output of the amplifier. As we increase the input voltage of the amplifier the output voltage of the amplifier is 5 times as large. This output of the amplifier is the input of the phase shifters. We scanned at the different frequencies to see how the gain of the amplifier could affect the output of the phase shifters. After observing our results, we found out that the different frequencies did not have that much of a phase shift difference. These results match the datasheet for both of the LM358 Amplifier and the JSPHS-1000+ Phase Shifter.
PCB 1
![Phase Shift vs. Control Voltage (4).png](https://static.wixstatic.com/media/d427e6_415861cbbbb54e54a216d0c501c8b435~mv2.png/v1/fill/w_847,h_480,al_c,q_90,usm_0.66_1.00_0.01,enc_auto/Phase%20Shift%20vs_%20Control%20Voltage%20(4).png)
PCB 1 Results
PCB 2
![Phase Shift vs. Control Voltage (5).png](https://static.wixstatic.com/media/d427e6_405ff3e28545449fa9ca950303aed154~mv2.png/v1/fill/w_846,h_484,al_c,q_90,usm_0.66_1.00_0.01,enc_auto/Phase%20Shift%20vs_%20Control%20Voltage%20(5).png)
PCB 2 Results
PCB 3
![Phase Shift vs. Control Voltage (6).png](https://static.wixstatic.com/media/d427e6_4a81db9dffd84d07b2ae3503d9b20ecb~mv2.png/v1/fill/w_847,h_485,al_c,q_90,usm_0.66_1.00_0.01,enc_auto/Phase%20Shift%20vs_%20Control%20Voltage%20(6).png)
PCB 3 Results
PCB 4
![Phase Shift vs. Control Voltage (7).png](https://static.wixstatic.com/media/d427e6_e69edbbd9aa543dfa36e4162393f979a~mv2.png/v1/fill/w_841,h_481,al_c,q_90,usm_0.66_1.00_0.01,enc_auto/Phase%20Shift%20vs_%20Control%20Voltage%20(7).png)
PCB 4 Results
Images
PCB 1
![Image_of_PCB1_Setup02.jpg](https://static.wixstatic.com/media/d427e6_b8b8af5780b14aae8f2de0e5c0717a90~mv2.jpg/v1/fill/w_849,h_637,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/Image_of_PCB1_Setup02.jpg)
PCB 1 Set Up
PCB 2
![IMG_0322_edited.jpg](https://static.wixstatic.com/media/d427e6_e8e42db4a1244d36ab674b91481f5e0f~mv2.jpg/v1/crop/x_48,y_163,w_2587,h_1930/fill/w_853,h_636,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/IMG_0322_edited.jpg)
PCB 2 Set Up
PCB 3
![Image_of_PCB03.jpg](https://static.wixstatic.com/media/d427e6_165caa0b35db484b843dcde54a598f3a~mv2.jpg/v1/fill/w_853,h_640,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/Image_of_PCB03.jpg)
PCB 3 Set Up
PCB 4
![Image_of_PCB04_02.jpg](https://static.wixstatic.com/media/d427e6_af90c35a84e14afa82660c5c74804192~mv2.jpg/v1/fill/w_852,h_639,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/Image_of_PCB04_02.jpg)
PCB 4 Set Up
PCB Fronts
![Image_of_Final_Soldered_PCB.jpg](https://static.wixstatic.com/media/d427e6_025c59116f3b43a18af9e993f486e152~mv2.jpg/v1/fill/w_848,h_636,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/Image_of_Final_Soldered_PCB.jpg)
All PCB Front
PCB Back
![Bottom_of_PCB_Soldered_Grounds.jpg](https://static.wixstatic.com/media/d427e6_9dff2b0ac4b648b3b8800d3a688838c3~mv2.jpg/v1/fill/w_848,h_636,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/Bottom_of_PCB_Soldered_Grounds.jpg)
All PCB Back