Download presentation
Presentation is loading. Please wait.
1
Passive Intermodulation (PIM) testing
Jan-20 Company Confidential
2
What is Passive Intermodulation (PIM)
TX signals at site Passive Intermodulation (PIM) Passive Intermodulation (PIM) F1 F2 IM 3 IM 3 IM 5 IM 5 IM 7 IM 7 IM 9 IM 9 PIM = interference PIM = new frequencies generated by Tx signals at a cell site when they encounter “non-linear” junctions in the RF path PIM falling in an operator’s uplink can elevate the noise floor: ▪ Dropped calls ▪ Access failures ▪ Slower data rates Jan-20 Company Confidential
3
What is a non-linear junction?
Linear junctions Current Voltage Current increases linearly with applied voltage. High pressure, metal-to-metal contacts Welded or soldered connections. Current Voltage Non-Linear junctions Current does not increase linearly with voltage. Low pressure, metal-to-metal contacts Oxide layers on metal surfaces Arcing across small air gaps or cracks Jan-20 Company Confidential
4
What is non-linear at a cell site?
Loose metal-to-metal contacts Poorly terminated RF connectors Metal flakes inside connectors Loose RF connectors Metal flashing on rooftops Loose rivets, screws, etc. Rusty / corroded surfaces Non-linear materials Nickel / Steel Ferrite Jan-20 Company Confidential
5
What does PIM look like at the site?
Broad band interference Narrow band spikes Jan-20 Company Confidential
6
What does PIM look like to the operator?
PIM Repair High average noise level BUSY QUIET BUSY QUIET Lower average noise level Jan-20 Company Confidential
7
Where does PIM occur? F1 F2 IM 3 IM 5 IM 7 IM 9 2*F2–1*F1 3*F2–2*F1 4*F2–3*F1 5*F2–4*F1 2*F1–1*F2 3*F1–2*F2 4*F1–3*F2 5*F1–4*F2 PIM occurs at mathematical combinations of the Tx frequencies F1 = 1930 MHz F2 = 1945 MHz IM3 = (2*1930) – (1*1945) = MHz IM3 = (2*1945) – (1*1930) = MHz IM5 = (3*1930) – (2*1945) = MHz IM5 = (3*1945) – (2*1930) = MHz IM7 = (4*1930) – (3*1945) = MHz IM7 = (4*1945) – (3*1930) = MHz IM9 = (5*1930) – (4*1945) = MHz IM9 = (5*1945) – (4*1930) = MHz Jan-20 Company Confidential
8
What is the bandwidth of PIM signals?
200 KHz 600 KHz 1 MHz 1.4 MHz 1.8 MHz PIM bandwidth increases as carrier bandwidth increases PIM bandwidth increase with PIM order F1 = 200 KHz F2 = 200 KHz IM3 bandwidth = 3* 200 KHz = 600 KHz IM5 bandwidth = 5* 200 KHz = 1000 KHz = 1 MHz IM7 bandwidth = 7 * 200 KHz = 1400 KHz = 1.4 MHz IM9 bandwidth = 9 * 200 KHz = 1800 KHz = 1.8 MHz Jan-20 Company Confidential
9
Can one wide band carrier generate PIM?
5 MHz 5 MHz 5 MHz 5 MHz 5 MHz 5 MHz 5 MHz 5 MHz 5 MHz IM 3 IM 5 IM 7 IM 9 YES ! The wideband signal is composed of individual sub-carriers Carrier bandwidth = 5 MHz IM3 bandwidth = 3* 5 MHz = 15 MHz IM5 bandwidth = 5* 5 MHz = 25 MHz IM7 bandwidth = 7 * 5 MHz = 35 MHz IM9 bandwidth = 9 * 5 MHz = 45 MHz Jan-20 Company Confidential
10
Why are we just now seeing this problem?
Before: Simple antennas Single bands per feeder Narrow carrier bandwidths Tx and Rx on separate feeders >50 dB Tx/Rx isolation! -50 dB -50 dB PIM Rx Tx Rx Jan-20 Company Confidential
11
Why are we just now seeing this problem?
Today: Complex antennas More RF connections Multiple bands per feeder Wider bandwidth carriers Tx and Rx combined on each feeder ▪ More potential PIM sources ▪ Increased probability of low order products ▪ No Tx/Rx isolation PIM Tx/Rx 850/1900 Tx/Rx 850/1900 Jan-20 Company Confidential
12
What is the solution? Eliminate non-linearity so that multiple frequencies can peacefully co-exist! Choose site locations wisely Choose RF components wisely Install carefully Verify linearity using a PIM test LTE GSM UMTS CDMA Jan-20 Company Confidential
13
How does PIM test equipment work?
Tx combiner Must be low PIM ! F1 Duplexer DUT TX F2 PIM Load IM RX Receiver Transmits two test frequencies High power (2x 20W typical) Measures signal level at the IM frequency Jan-20 Company Confidential
14
Why do we measure IM3 ? F1 F2 IM 3 IM 3 A A Noise Floor IM 11 IM 9 IM 7 IM 5 IM 5 IM 7 BTS Uplink (Rx) BTS Downlink (Tx) IM3 is the highest magnitude / most accurate to measure IM3 “characterizes” the linearity of the system Reducing IM3 reduces all PIM products Jan-20 Company Confidential
15
What test frequencies should I use?
Exact frequencies used not critical F1 & F2 spaced far apart to put IM3 in Rx band Guard band frequencies recommended for fixed tone tests F1, F2 & IM3 must all be able to pass through the system Jan-20 Company Confidential
16
What might block PIM test frequencies?
850 1900 Antennas MHz MHz Tower Mounted Amplifiers (TMA) Filters Lightning surge protectors Sweep test to verify Use correct PIM test set By-pass frequency limiting devices Jan-20 Company Confidential
17
What is the preferred test process?
START Site Master Sweep test DTF Repair PIM Master Noise Floor Static PIM vs. TIME Dynamic PIM vs. TIME Save Results END Repair DTP Repair Jan-20 Company Confidential
18
Anritsu PIM test solutions
Jan-20 Company Confidential
19
First Generation PIM Master
Introduced PIM Master™ Dec. 2010 Distance-to-PIM™ technology 43 to 46 dBm output power (20 to 40 W) Controlled using: BTS Master Cell Master Site Master Spectrum Master Three models: 850 MHz, 900 MHz, 1900/2100 MHz Jan-20 Company Confidential
20
New Second Generation PIM Master
World’s first: battery operated high power PIM analyzer Lightweight / small size one-half the weight one-forth the size 25 to 46 dBm (0.3 to 40 W) Distance-to-PIM™ No external controller required Nine models: 700 MHz (U/L), 800 MHz, 850 MHz, 900 MHz 1800 MHz, 1900 MHz, 1900/2100 MHz 2100 MHz, 2600 MHz Jan-20 Company Confidential
21
MW82119A – PIM testing at top of the tower
Remote Radio Head (RRH) sites Fiber & DC power to RF unit RF path is jumper cable + antenna PIM sources reduced, but not eliminated Traditional test equipment not useful: Heavy No AC power MW82119A is the solution: Light weight Battery operation Remote control option Jan-20 Company Confidential
22
MW82119A – Higher capacity DAS installations
Distributed Antenna Systems (DAS): Many PIM sources Metal near antennas Many RF connections Operators co-located on DAS More frequencies mixing together Increased probability of IM in RX band MW82119A is the solution: Battery operation for remote testing Low power capability Distance-to-PIM technology Jan-20 Company Confidential
23
MW82119A – Simplifies site testing
Rooftop sites: Access challenges: Ladders No elevator Many external PIM sources: Metal on building Rusty equipment MW82119A is the solution: Light weight / small size Distance-to-PIM technology Jan-20 Company Confidential
24
MW82119A - Key features Parameter Specification Small size
350 x 314 x 152mm (13.8 x 12.4 x 6.0in) Light weight 9 kg to 12 kg * (20 lb to 27 lb) Battery operation > 3.0 hours Wide power range 25dBm to 46dBm (0.3W to 39.8W) Residual PIM 2x 43dBm Distance-to-PIM™ YES PIM vs. Time Swept PIM Noise floor Remote Control GPS option Full-featured PIM test set! * - Weight varies by frequency option Jan-20 Company Confidential
25
MW82119A – Available models Frequency Option Model Number F1 F2 IM
700 MHz (L/U) MW82119A-0700 734 – MHz 745 – 768 MHz 698 – 716 MHz / 779.5 – 804 MHz 800 MHz MW82119A-0800 791 – 795 MHz 811.5 – 821 MHz 832 – 862 MHz 850 MHz MW82119A-0850 869 – MHz 881.5 – 894 MHz 824 – 849 MHz 900 MHz MW82119A-0900 925 – MHz 951.5 – 960 MHz 880 – 915 MHz 1800 MHz MW82119A-0180 1805 – MHz – 1880 MHz 1710 – 1785 MHz 1900 MHz MW82119A-0190 1930 – MHz 1950 – 1990 MHz 1870 – 1910 MHz 1900/2100 MHz MW82119A-0193 1930 – 1940 MHz 1955– 1995 MHz 1850 – 1910 MHz 2110 – 2155 MHz 1710 – 1755 MHz 2100 MHz MW82119A-0210 2110 – MHz 2130 – 2170 MHz 1920 – 1980 MHz / 2050 – 2090 MHz 2600 MHz MW82119A-0260 Jan-20 Company Confidential
26
MW82119A – User interface RF indicator RF output Emergency stop button
Menu key On / Off key Arrow keys Touch screen display Keypad Jan-20 Company Confidential
27
MW82119A – User interface Two USB ports External power input
AC adapter Automotive adapter Ethernet Remote control Two USB ports Power sensor Flash drive Mini USB port PC connectivity SMA (f) (w/Option 31) GPS antenna Jan-20 Company Confidential
28
MW82119A – Remote control Control PIM test from remote location
Firmware v1.04 (or greater) ZyXEL MWR102 router (or equiv.) Download application from Anritsu website and install on any Windows OS device with WiFi Range: >100m (328FT) line-of-site Jan-20 Company Confidential
29
MW82119A – PIM vs. Time measurement
F1 and F2 fixed PIM magnitude vs. time Visual indication of PIM stability Peak PIM held for Pass/Fail Used for dynamic PIM testing Tapping on RF connections Limit Line Jan-20 Company Confidential
30
MW82119A – Noise Floor measurement
Measures IM frequency with transmitters turned OFF Verify no external interference at test frequency External interference Jan-20 Company Confidential
31
MW82119A – Swept PIM measurement
Multiple PIM signals on combining in and out of phase 45 dB F1 fixed, F2 swept F2 fixed, F1 swept PIM magnitude vs. frequency Shows worst case PIM level 45 dB variation due to phasing! Jan-20 Company Confidential
32
MW82119A – Distance-to-PIM™ (DTP) measurement
Antenna PIM source 28 m (59 FT) beyond antenna F1 fixed, F2 swept PIM magnitude vs. distance The fastest way to locate PIM See PIM beyond the antenna 6 markers + marker table Jan-20 Company Confidential
33
MW82119A – Enhanced Resolution DTP
Standard resolution reports one PIM source at 16.7m Enhanced resolution reports two PIM sources, 15.7m and 17.4m Improves ability to see closely spaced PIM sources Predictions clearly marked by red bars Location for each prediction automatically displayed Speeds DTP trace interpretation 0m 18m 16m load 2m 2x PIM sources Jan-20 Company Confidential
34
MW82119A – Distance-to-PIM™ (DTP) overlay
Compare two DTP measurements Automatically displays distance between peaks Useful for: Showing “before” & “after” results Showing distance to object in front of antenna Saving the measurement keeps both traces for reports Overlay trace Active trace Relative distance Jan-20 Company Confidential
35
MW82119A – Display options Default Colors Black and White Night Vision
High Contrast Invert Black and White Jan-20 Company Confidential
36
MW82119A – Report Management
Manage PIM data using Line Sweep Tools (LST) Familiar user interface Add markers / adjust scale Single site report combining VSWR & PIM results Tabular PIM report option Jan-20 Company Confidential
37
MW82119A – Designed for outdoor use
2 to 3 hour Battery Life Replaceable Same as other Anritsu HHs Production tested for reliability 50 hour burn-in 2 hour thermally cycled Designed tested for reliability HALT Test Vibration Test Shock Test Drop Test Designed and tested like all Anritsu Handhelds Jan-20 Company Confidential
38
MW82119A – Standard Accessories
Part Number Description R Soft Carrying Case R Shoulder Strap R Connector Saver 633-75 Li-Ion Battery Pack R AC/DC Power Adapter (country dependent) AC Power Cable R Automotive 12V DC Adapter R Ethernet Cable, 213 cm (7 ft) USB Cable, 305 cm (10 ft) R Stylus with Coiled Tether Anritsu Tool Box w/Line Sweep Tools DVD Disc Jan-20 Company Confidential
39
Optional Accessories 2000-1745-R - Backpack Accessory Kit
R – Transit case (Holds MW82119A only) R – Transit case (Holds MW82119A plus accessories) (accessories not included) R - Hard Case Accessory Kit Jan-20 Company Confidential
40
Light weight Battery operated Full featured PIM Analyzer
PIM Master MW82119A Light weight Battery operated Full featured PIM Analyzer Jan-20 Company Confidential
41
PIM Master MW82119A Demonstration Jan-20 Company Confidential
Similar presentations
