LDMOS RF AMPLIFIER LINEARIZATION USING POWERSDR MRX …flarc.net/eme-info/PDF/N1JEZ-1.pdf · ldmos...

of 47 /47
LDMOS RF AMPLIFIER LINEARIZATION USING POWERSDR MRX PURE SIGNAL Mike Seguin, N1JEZ MID-A TLANTIC STATES VHF CONFERENCE 2014 1

Transcript of LDMOS RF AMPLIFIER LINEARIZATION USING POWERSDR MRX …flarc.net/eme-info/PDF/N1JEZ-1.pdf · ldmos...

LDMOS RF AMPLIFIER LINEARIZATION USING

POWERSDR MRX PURE SIGNAL Mike Seguin, N1JEZ

MID-ATLANTIC STATES VHF CONFERENCE 2014

1

OPENHPSDR HERMES

• DUC/DDC ARCHITECTURE

• CONTINUOUS UNINTERRUPTED RECEIVE COVERAGE FROM 10KHZ TO 55MHZ

• MULTIPLE RECEIVER SUPPORT @ 48/96/192/384 KHZ BW

• FULL DUPLEX OPERATION - ANY SPLIT OVER ENTIRE 160M TO 6M RANGE

• 500MW RF OUTPUT ON 160 – 10M, 350MW ON 6M

• SOFTWARE-SELECTABLE 31dB INPUT ATTENUATOR IN 1dB STEPS

2

OPENHPSDR HERMES

3

POWERSDR MRX PS

4

PURE SIGNAL

• DR. WARREN PRATT, NR0V – PRIMARY ARCHITECT OF PURE SIGNAL • RECIPIENT - ARRL TECHNICAL INNOVATION AWARD 2014

• "PREDISTORTION“ - THE SOFTWARE "PREDISTORTS" THE INPUT SIGNAL

TO THE AMPLIFIER TO CORRECT FOR NON-LINEARITIES IN THE OUTPUT

• “ADAPTIVE PREDISTORTION” - CONTINUOUSLY MONITORS OUTPUT VS INPUT AND MAKES CHANGES BASED ON VARYING CONDITIONS

• FINITE “CORRECTION BANDWIDTH” OF 40 KHZ OR +/- 20 KHZ FROM THE CENTER TRANSMIT FREQUENCY

5

PURE SIGNAL

6

Hermes Class A Driver

LDMOS Amplifier

Anritsu MS2721

Dielectric Wattmeter

Bird Sniffer

Bird kW Load

TEST SETUP

50.140 MHz TWO TONES @ 300 WATTS AVG

7

FEEDBACK SIGNAL IS SET 1 dB BELOW ADC OVERLOAD

CLASS A DRIVER RD16HHF1 MOSFET

0.5 watts in – 5.0 watts out

8

LDMOS AMPLIFIER NXP BLF-178

6M kW

9

Yaesu FT-817

FUNcube HDSDR

software

Pad

IF TAP

TEST SETUPS - OTA

ANAN-100

FT-817 using 68.33 MHz IF Tap FUNcube Dongle HDSDR Software

10

Hermes Based PowerSDR mRX PS

THE PERFECT AMPLIFIER

11

IN REALITY….

12

PURE SIGNAL CORRECTION

13

HERMES WITH PURE SIGNAL OFF

IMD3 = -46.30 IMD5 = -52.91

14

HERMES WITH PURE SIGNAL ON

IMD3 = -63.93 IMD5 = -77.71

15

HERMES WITH PURE SIGNAL OFF PowerSDR mRX PS

16

HERMES WITH PURE SIGNAL ON PowerSDR mRX PS

17

CLASS A DRIVER WITH PURE SIGNAL OFF

IMD3 = -40.16 IMD5 = -49.82

18

CLASS A DRIVER WITH PURE SIGNAL ON

IMD3 = -61.20 IMD5 = -75.25

19

20

LDMOS WITH PURE SIGNAL OFF

IMD3 = -38.02 IMD5 = -41.90

21

LDMOS WITH PURE SIGNAL ON

IMD3 = -54.48 IMD5 = -65.18

22

Hermes Driver LDMOS

HDSDR WATERFALL OTA

PURE SIGNAL OFF

PURE SIGNAL ON

23

AMPVIEW CLASS AB SSB 1.5A IDQ

24

AMPVIEW CLASS AB SSB 1.5A IDQ

25

AMPVIEW CLASS AB SSB 2A IDQ

26

SUMMARY CLASS AB

• PURE SIGNAL LOWERS IMD

• PROVIDE A GOOD CLEAN FEEDBACK SIGNAL FOR PURE SIGNAL

• PAY CLOSE ATTENTION TO THE FEEDBACK SIGNAL LEVEL

• MY SIGNAL IS TOO CLEAN – NOW OTHER OPERATORS ARE GOING TO TUNE RIGHT NEXT TO ME AND SPLATTER ALL OVER ME

• POWERSDR MRX PS HAS A NEW ADDED FEATURE ON THE RIGHT SIDE OF THE SCREEN

27

SPLATTER MODE

28

SPLATTER MODE ON

29

CLASS B LINEARIZATION?

• Is Pure Signal robust enough?

• Normal Class AB bias @ 1.5 A

• ~ 75 watts heat dissipated

• Class B set for 100 ma

• ~ 5 watts heat dissipated

30

LDMOS CLASS B WITH PURE SIGNAL OFF

IMD3 = -22.40 IMD5 = -28.36

31

IMD3 = -55.57 IMD5 = -63.04

LDMOS CLASS B WITH PURE SIGNAL ON

32

HDSDR WATERFALL OTA

PURE SIGNAL OFF

PURE SIGNAL ON

33

LDMOS CLASS B WITH PURE SIGNAL OFF

-31.8 in 3 kHz -31.2 Peak

34

LDMOS CLASS B WITH PURE SIGNAL ON WHY DOES THE SIGNAL INCREASE?

-28.3 in 3 kHz -28.0 Peak

35

LDMOS CLASS B WITH PURE SIGNAL OFF

Channel Pwr -28.49 Pwr Density -63.27 dBm/Hz

36

LDMOS CLASS B WITH PURE SIGNAL ON WHY DOES THE SIGNAL INCREASE?

Channel Pwr -25.20 Pwr Density -59.97 dBm/Hz

37

AMPVIEW CLASS B 2 TONE 100MA IDQ

38

AMPVIEW CLASS B 2 TONE 100MA IDQ

39

AMPVIEW CLASS B SSB 100MA IDQ

40

AMPVIEW CLASS B SSB 100MA IDQ

41

SUMMARY CLASS B

• PURE SIGNAL LOWERS IMD

• IT LINEARIZES THIS LDMOS CLASS B AMP

• MY SIGNAL IS TOO CLEAN – NOW OTHER OPERATORS ARE GOING TO TUNE RIGHT NEXT TO ME AND SPLATTER ALL OVER ME

• JUST TURN OFF PURE SIGNAL

42

THE BLUE THUNDER – 2 PILL WONDER!

Property of W1GHZ

43

28 MHZ AMPLIFIER – 2 PILL DEVICES ARE 2SC2290 - 60 WATTS PEP EACH

AMP TESTED AT 125 WATTS

44

BLUE THUNDER WITH PURE SIGNAL OFF

IMD3 = -17.89 IMD5 = -27.74

45

BLUE THUNDER WITH PURE SIGNAL ON

IMD3 = -47.60 IMD5 = -53.75

46

LDMOS RF AMPLIFIER LINEARIZATION USING

POWERSDR MRX PURE SIGNAL Mike Seguin, N1JEZ

QUESTIONS?

47