Objectives Typical IMD Levels and Applications Emission Monitoring Solutions Measuring without Disrupting

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2 Objectives Typical IMD Levels and Applications Emission Monitoring Solutions Measuring without Disrupting Low PIM Filtering Solutions - Building Blocks for Reducing Uncertainty of Measurement High-Pass/Low-Pass Duplexer (HP/LP) Band-Pass/Band-Stop Duplexer (BP/BS) Duplexers (BP/BP, LP/BP) Triplexers (BP/BP/BP) Band-Reject Filters with Band-Extenders (BRF/BE) Build Your Own IMD Test Setups - Control your Dynamic Range The Blockers are everywhere: New Filtering Solutions The Quadraplexer : BRF/BP/BP Triple Beat Test - a Real Challenge The Road Map to a Complete and Customized Switched Test System Q/A 2

3 [dbm] Typical IMD Levels and Applications IP3[dBm] P[dBm] IM[dBm] IMD[dBc] IM 3 rd = (2*f1-f2) and (2*f2-f1) IMD = P-IM IMD IPn P n 1 For n=3: IP3 = P+IMD/2 5 th 3 rd f1 f2 3 rd 5 th Tx P[dBm] IM[dBm] IMD[dBc] Application f PIM is IM created by a Passive Source 2x(+43) -113* 156 Base Station, PA, Antenna: High-Power 2x(+43) Distributed Antenna Systems (DAS) 2x(+26), (+26)+(+16), (+26)+(-16) Semi-con., Small Cell, Chipsets, Switches, Tunable Caps, IC, etc.: Low-Power 2x(+43) PIM Analyzers Can you tell which measurement is tougher? Answer: (43 26) Only 10dBm difference! 1dBm reduction in power carriers (f1 and f2) yields ~2.2dBm reduction in IM 3 rd 3

4 Emission Monitoring Solutions: Near and Far Zones Carriers Low PIM 50Ω Termination Near Zone (LPF) Far Zone (HPF) Non- Reflective SPDT Notes: Emission monitoring is also Forward IMD measurement The HPF and BRF need to reject the carriers such that -60dBm max. can travel to the spectrum analyzer Avoid reflected waves back to the DUT or to the source Low PIM 50Ω Termination (marked with a in this presentation) is used only if the carriers are passing through The SPDT is non-reflective, but not specified for PIM, since carriers don t travel through Spectrum Analyzer 4

5 BP/BS Duplexer Applications Traditional Setup Improved Setup Often used to increase the Dynamic Range of the S/A by attenuating the unwanted signal from mixing Attenuator S11 Matched Band-Reject Filter Often used to improve Impedance Match with the DUT, while drawing more power from the PA Attenuator S11 Matched Band-Pass Filter TDD FDD 5

6 BP/BS Duplexer A complete list of available Band- Pass/Band-Stop duplexers is available at the following link: tach/1/_plk287_1_lowpimhp.pdf If your specific need is not covered here, contact K&L for a custom design. 6

7 BP/BS Typical Data 7

8 BP/BS Typical Data The flatter the PIM response, the fewer the IMD sources. 8

9 High-Pass/Low-Pass Duplexer Applications: Emission Monitoring 2nd and 3rd Harmonic Tests from a Single Tone fo PA fo DUT Spectrum Analyzer 2fo, 3fo. Notes: The LPF passes the fundamental carrier and rejects the Harmonics, preventing them from entering the DUT The HPF terminates Harmonics generated by the PA 9

10 Low PIM High-Pass and Low-Pass Filters 10

11 Typical Data (Two +43dBm Tones) 11

12 Two Tones-Single Amp-IMD in Band Setup #1a Applications: Two Tones - 3rd IM Reflected and Forward in the Band Tx Tx DUT Non- Reflective SPDT Notes: Signals are combined pre-amplification state. Single amplifier produces two-tones and large IMD levels. Isolator is an IMD source. Spectrum Analyzer Tx filter is required of high rejection levels >-115dBc. Carriers are rejected back into the isolator. filter is required to attenuate the carriers to <-60dBm, to reduce IM products inside the Spectrum Analyzer. Hard to obtain low IMD base line. 12

13 Two Tones-Single Amp-IMD in Band Setup #1b Tx DUT Spectrum Analyzer Notes: Reflected Mode only Difficult to obtain a base line 13

14 Two Tones-Two Amps-IMD in Band Setup #2a TX1 Tx Tx DUT TX2 Non- Reflective SPDT Notes: Most popular; cheap, easy to assemble Amplifiers seem to be isolated by roughly 50dB Spectrum Analyzer Reflected TX1 and TX2 signals are travelling back to isolators, by nature ferromagnetic devices Secondary IM products are generated, due to reflections, which tends to raise the base line of the setup Tx filter must present at least 100dB rejection to the band, preventing IM products from the iso-coupler from travelling to the Spectrum Analyzer filter needs to present 100dB to Tx band, reducing +43dBm tones from mixing inside the Spectrum Analyzer Amplifiers need to present extra 3.5dB gain to compensate for the 3dB hybrid and isolators 14

15 Two Tones-Two Amps-IMD in Band Setup #2b TX1 Tx DUT TX2 Spectrum Analyzer Notes: Reflected Mode only 15

16 IMD Test Setup #3 Applications: Inter-Cell Interference in Forward mode Tx1 Tx1 Tx Tx2 Tx2 DUT Spectrum Analyzer Notes: Two narrow band filters substituted for the -3dB Hybrid The output duplexer covers the entire down-link and up-link bands Input duplexer must be of high quality (always), since it s difficult to pinpoint IMD sources 16

17 Duplexers (BP/BP) 100dB Tx- & 161dBc PIM (Two +43dBm Tones) A complete list of available Low PIM Band-Pass/Band-Pass Duplexers is available at the following link: attach/2/_plk315_1_daslowpimds.pdf If your specific need is not covered here, contact K&L for a custom design. 17

18 Two Signals-BP/BP/BP (Triplexer)-IMD Test Setup #4a Tx1 Tx1 Tx1 Tx2 Tx2 DUT Tx2 Non- Reflective SPDT Notes: IM test in Reverse and Forward mode Base line is easy to maintain All ports are tuned for -20dB return loss Easy to maintain and debug problems Spectrum Analyzer 18

19 Two Signals-BP/BP/BP (Triplexer)-IMD Test Setup #4b Tx1 Tx2 Spectrum Analyzer Tx1 Tx2 DUT A complete list of available Low PIM Triplexers is available at the following link: 3GPPTriplexers.pdf If your specific need is not covered here, contact K&L for a custom design. Notes: Amplifiers are isolated by 75dB filter presents 100dB in Tx band Tx1 and Tx2 are relatively narrow (about 1/3 of down-link bandwidth), reducing the out-of-band noise of the amplifiers Tx2 can be dedicated to a Blocker signal Triplexer can be self-tested - easy to maintain 19

20 Two Signals-Both Ports of DUT-IMD Test Setup #5 Tx1 Tx1 Tx1 Tx2 DUT Tx2 Tx2 Non- Reflective SPDT Spectrum Analyzer Notes: DUT is subjected to two signals, one from each port Filtering the signals provides flow and avoids reflections, reducing possible IMD sources 20

21 Low PIM Triplexers (BP/BP/BP) f1 f2 1.5dB f3 f4 f5 f6 RX TX1 TX2 75 db 100 db Triplexers can be self- tested Easy to maintain the base line Tx1 Tx2 Tx1 Tx2 Spectrum Analyzer 21

22 The Blockers are Everywhere! BRF/BPF/BPF (Quadraplexer) Tx BRF Tx+ Electrical Scheme Frequency Response Notes: Tx,, and BRF are isolated by 75dB All three filters are tuned for 20dB return loss to reduce uncertainty of measurement BRF provides 20dB of match over all specified Blockers 22

23 Extending the Passband of the Triplexer- Reverse IMD Tx Tx Spectrum Analyzer DUT BRF Tx+ Blockers Non- Reflective SPDT The Quadraplexer: Blocker Signal Gen. Enables all combinations of Blockers and Tx signals 23

24 LTE Band 2: Actual Data Tx: MHz (1880MHz) : MHz (1960MHz) Blockers: 80MHz, 1800MHz, 3800MHz, and 5800MHz 24

25 LTE Band 2: Actual Data (continued) 25

26 Tx + Blocker IMD Test Data Tx1 1855MHz Tx2 1775MHz 3 rd IMD 1935MHz Enables mixing the Tx signal with many Blockers through the BRF Limited only by the BRF upper-passband match Easy to maintain 26

27 LTE Band 2: Actual Data (continued) 27

28 LTE Band 2: Tx signal and Blockers 28

29 Tx + Blocker -IMD Test Setup #6a Tx Tx Tx BRF Tx+ DUT BRF Tx+ Blocker Signal Gen. Non- Reflective SPDT Spectrum Analyzer Notes: Reverse and Forward IMD measurements Easy to maintain and debug 29

30 Tx + Blocker Port Swapping-IMD Test Setup #6b Spectrum Analyzer SP2T Non- Reflective Tx SP2T Non- Reflective Tx Tx DUT BRF Tx+ Blockers Blockers BRF Tx+ Non- Reflective SP4T Blocker Signal Gen. Enables exposing the DUT to one Tx signal and any Blockers with port swapping capability Enables measurements for Reverse and Forward 30

31 Mix-n-Match (LTE Band 7) Triplexer/Duplexer BPF BPF BPF DUT BPF BPF Spectrum Analyzer 31

32 Triple Beat & 3rd IMD for RF Switches Triple Beat and IMD for RF Switches emulates two Transmit carriers of the mobile up-link, separated by 1MHz, entering the DUT, along with a Jammer ( Blocker ), representing a weaker signal in the mobile down-link (Receive) band, from a different system. IM 3 rd are f3-(f2-f1) and f3- (f2+f1) Concerns with the proposed block diagram : The two Tx carriers mix with the Jammer in the CW source Limited isolation between the amplifiers - return loss limit. Jammer signal travels directly into the Spectrum Analyzer 32

33 Triple Beat Filter Based - Phase 1 TX1 Tx Tx DUT TX2 Spectrum Analyzer Blocker Source Notes: Jammer CW source is now protected from the two TX signals One problem remains: Energy of TX1 and TX2 is reflected back from Tx Filter and DUT, F1 goes to AMP1 and AMP2 and vice versa Further mixing is taking place at the isolators 33

34 Triple Beat Filter Based - Phase 2 f1 f1 f1+f2 f2 f2 DUT Spectrum Analyzer IM f3 f3 IM in Band = f3-(f2-f1) & f3+(f2-f1) Notes: Hi Q ceramic puck filter can provide ~40dB rejection Adding isolators can increase the isolation to ~60dB Carriers are terminated after passing through the DUT Depending on Jammer power level, this setup should be able to provide a good base line 34

35 Triple Beat Filter Based - Phase 3 Introducing the narrow band BP/BS Duplexer 2MHz The Band-Pass filter is passed f3 and rejects the IMD products by 40dB. The Band-Stop filter passes the IMD products and rejects f3 by 40dB. The Band-Pass filter (or Band-Stop filter) can be terminated, providing a broadband match to common port. 35

36 Triple Beat Filter Based - Phase 4 f1 f1 f1+f2 f2 f2 DUT IM f3 f3 Spectrum Analyzer Notes: Units enclosed in dashed line are all integrated Number of external connections and jumpers kept to a minimum 36

37 The Road Map to Test Rack System ATE Integrations Supports automated production testing of wireless systems and semiconductor product families covering all LTE bands Provides emission monitoring while maintaining a good impedance match with the device under test (DUT) Can be used to measure IM products and NF and for Triple Beat tests 37

38 Switch Matrix Next Generation Matrix Modular Architecture flexibility reconfigurable expandable Compact Structure reduce 10X10 rack space from 4U to 3U Trouble-free Maintenance field serviceable field upgradable Removable Power Supply easy access redundant power supplies available Fast Switching Time < 50ms Interface Options Ethernet (TCP/IP), HTTP Server, LabVIEW-based Web Services, RS-232, USB, GPIB,... Power Module (Mounts Vertically for 3U and 4U Enclosures) Mounting Brackets for Switches 2U Model 38

39 Custom Solutions Low PIM Test Station for. Cell Phone Tester for.. 39

40 Coaxial Switch - Data 40

41 The Road Map to Test Rack System (cont.) 41

42 Interface Options Most switchable RF devices provide a combination of remote and local interfaces. A typical unit is equipped with one or two of the following options: o SNMP SNMP v.1 SNMP v.3 (coming soon) o LabVIEW-based Web Services o GPIB o Ethernet (Built-in Web Server) o USB o RS-232 o CAN-bus -- load the Lua VISA wrapper require "visa" -- open connection to equipment if interface == "GPIB" then -- use GPIB interface 0 at address 16 c = visa.open "GPIB0::16::INSTR" else if interface == "SERIAL" then -- use serial (RS-232, RS-485, etc) interface 1 c = visa.open "ASRL1::INSTR" else if interface == "TCP" then -- use TCP/IP over interface 0 c = visa.open "TCPIP0:: ::7::SOCKET" end -- set switch 1 to position 2 c:write "CT1.2" 42

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