Mitigating Interference & Maximizing Throughput in 700MHz for SCADA Paul Reid and Kathy Shaft (GRE) October 2018
WAS SPUN OUT OF 2
3 Phoenix US Headquarters US Headquarters Technical Support Hub Repair Warehousing 3
GRE s current SCADA Network 60 BTS 470 Substations SCADA Metering Coop backhaul Operates in 700 MHz A band (lease) Plan to purchase at the end of lease Sectorized system using 3, 330 khz Channels Operating since 2006 Acadian equipment if failing and no longer supported so we needed to research a replacement Change in Vendor selection 4
Self Interference Temperature inversion Mitigation Techniques -Powered down sectors -Down-tilt antennas 5
External Interference We had no neighbors when we deployed. Verizon's LTE deployment started taking down substations (2010). Arcadian radios did not have adequate filtering Had to install external filters at all sites. 6
More External Interference Now FirstNet Moved in No Filter Filter 7
How will our new network avoid these issues? Chose Mimomax as our vendor. Worked with Salt River Project (Arizona) Purchased A Band Chose Mimomax We have 6 BTS radios installed and 16 Remotes. (on border of our network) Mimomax radios use khz channels Much better frequency reuse 20 channels vs. 3 Internal bandpass filter Impressive amount of data in a small channel 8
How to deploy when using the same band? Installed at all our substations last year 9
Start with Channel 4 4 5 6 10
Grid Automation Grid Modernization, Multi-use Field Area Network or Smart Grid Image: SRP FAN Presentation UTC 2018 11
Proposing a Field Area Network 12
The Steps We want a new or more capable network What area is coverage required..easy TO SOLVE What do we want to do with the network EASY TO SOLVE 13
The Steps We want a new or more capable network What area is coverage required..easy TO SOLVE What do we want to do with the network EASY TO SOLVE What capacity do our customers need NOT SO EASY TO SOLVE 14
The Steps We want a new or more capable network What area is coverage required..easy TO SOLVE What do we want to do with the network EASY TO SOLVE What capacity do our customers need NOT SO EASY TO SOLVE Spectrum Strategy what is available licensed from FCC or purchase? 15
The Steps We want a new or more capable network What area is coverage required..easy TO SOLVE What do we want to do with the network EASY TO SOLVE What capacity do our customers need NOT SO EASY TO SOLVE Spectrum Strategy what is available licensed from FCC or purchase? Re-use your LMR channels having migrated from 25kHz to 12.5kHz channels License additional frequencies from the FCC 900MHz 12.5kHz, 25kHz, Aggregate channel up to khz, also 100kHz and 200kHz blocks available Purchase 700MHz Upper A Block 2 x 1MHz 757-788MHz Purchase 900MHz Space Data Blocks available 901 941MHz 16
The Steps We want a new or more capable network What area is coverage required..easy TO SOLVE What do we want to do with the network EASY TO SOLVE What capacity do our customers need NOT SO EASY TO SOLVE Spectrum Strategy what is available licensed from FCC or purchase? Re-use your LMR channels having migrated from 25kHz to 12.5kHz channels License additional frequencies from the FCC 900MHz 12.5kHz, 25kHz, Aggregate channel up to khz, also 100kHz and 200kHz blocks available Purchase 700MHz Upper A Block 2 x 1MHz 757-788MHz Purchase 900MHz Space Data Blocks available 901 941MHz Design coverage to meet capacity across the network 17
The Steps We want a new or more capable network What area is coverage required..easy TO SOLVE What do we want to do with the network EASY TO SOLVE What capacity do our customers need NOT SO EASY TO SOLVE Spectrum Strategy what is available licensed from FCC or purchase? Re-use your LMR channels having migrated from 25kHz to 12.5kHz channels License additional frequencies from the FCC 900MHz 12.5kHz, 25kHz, Aggregate channel up to khz, also 100kHz and 200kHz blocks available Purchase 700MHz Upper A Block 2 x 1MHz 757-788MHz Purchase 900MHz Space Data Blocks available 901 941MHz Design coverage to meet capacity across the network but now we want to do more with the network!! 18
Spectrum Strategy 19
20 Channelization 20
21 Channelization TELEPROTECTION 21
Channelization TELEPROTECTION SCADA AMI BACKHAUL SUB STATION Mgmt. SPARE 22
23 23 Wireless Spectrum Selection Downlink NU L T1 T2 T3 T4 T5 T6 T7 T8 T9 T 10 T 11 T 12 T 13 T 14 T 15 T 16 T 17 T 18 NU L NU L R1 R2 R3 R4 R5 R6 R7 R8 R9 R 10 R 11 R 12 R 13 R 14 R 15 R 16 R 17 R 18 NU L Uplink
Capacity Requirements 24
What capacity do your customers need? 25
26 Capacity Raw Aggregate Data Rate Sensitivity for Data Rate (10-6 ) Modulation 12.5 khz 25 khz khz Modulation 12.5 khz 25 khz khz QPSK 80 kbps 160 kb/s 320 kbps QPSK -115 dbm -112 dbm -109dBm 16-QAM 160 kbps 320 kb/s 640 kbps 16-QAM -108 dbm -105 dbm -102dBm 64-QAM 240 kbps 480 kb/s 960 kbps 64-QAM -102 dbm -99 dbm -96 dbm 256-QAM 320 kbps 640 kb/s 1280 kbps 256-QAM -95 dbm -92 dbm -89 dbm 26
Radio Mobile Google Earth Network Coverage Plots 27
9 dbi Sector panel 11 dbi Sector Panel 16 dbi Sector Panel 12 and 15dBi Yagi s 9 dbi Panel 8dBi Panel 28
Radio Mobile Developed by Roger Coudé (Canada) VE2DBE since 1988. Commercial origins. Freeware/Donationware ($20 a year for commercial use) 29
Radio Link Path Analysis 30
Radio Mobile Export Path Models to Google Earth 31
GRE Design Process 32
GRE design process Migrated the legacy GRE CelPlanner project over to MiMOMax technology. Generated improved Terrain and Clutter databases in CelPlan format for the project. Devised a procedure for applying adequate Fade Margins based on path lengths. (ITU-R P.530-15 Model, 99.9% Availability) Defined new propagation model settings to reflect the new clutter dataset. Via post processing results from the analysis of each individual path, we determined what antennas were required at each Base Station Sector and each Remote Station. Carried out Automatic Frequency Planning based on the constraint that the spectrum was already in service on the legacy GRE network. Devised a channel plan that would support migration from the old system to the new MiMOMax solution. Delivered the latest CelPlanner project to GRE along with results in a Google Earth package. 33
GRE Terrain Database Developed a Digital Terrain Layer, converted from USGS 10m NED into CelPlan Topography format, across the whole state. 34
GRE Clutter Database Developed a Digital Clutter Layer, based on USGS NLCD Land Cover data carved with OSM road vectors, which was converted into CelPlan Morphology format. Tree heights were assigned as different values across the state to reflect the change in heights in different regions. 35
Clutter development Example of clutter data set generated with USGS NLCD Land Cover data, carved with OSM road vectors @ 5m resolution, exported in a format suitable for use in clutter conversion tool. 36
GRE Base Sector to Outstation Path Profile 37
Frequency Reuse Start with theoretical cellular pattern Exploit directional remote antenna Modify based on propagation modelling 38
GRE- CelPlan export of GRE network coverage, indicating channel for each sector. 39
Interference Consideration 40
Managing Interference Interference to and from other services in adjacent frequency bands Frequency reuse within the system In band interference to and from adjacent regions 41
42 42 Wireless Spectrum Selection Downlink NU L T1 T2 T3 T4 T5 T6 T7 T8 T9 T 10 T 11 T 12 T 13 T 14 T 15 T 16 T 17 T 18 NU L NU L R1 R2 R3 R4 R5 R6 R7 R8 R9 R 10 R 11 R 12 R 13 R 14 R 15 R 16 R 17 R 18 NU L Uplink
43 Enablers Low Noise Design Spectral Purity Adjacent Channel Power Rejection Linear PA design to reduce spectral regrowth and support higher order modulation 43
44 Adaptive Modulation Raw Data Rate QPSK QAM16 QAM 64 QAM 256 Bits Per Symbol 2b/sym 4b/sym 6b/sym 8b/sym More Range Depends on Link Factors Less Range N of Bits N of Pts= 2 Path Performance Ensures every RRU is operating at its most effective data rate Links are optimised for efficiency and throughput 44
45 The Full Duplex Advantage Increased Data Capacity Reduced Latency (More efficient in handling IP traffic) Duplexer provides excellent rejection of adjacent band interference 45
Tower Mapping Map exact location of all antennas on tower, along with RF details. Utilize for determining aperture for new antennas and interference analysis 46
Interference analysis To and from the new system Best to look at interference upfront.. as opposed to costly surprises after design/installation. Take into account equipment specs, tower/antenna mapping, RF & site surveys and possible near site issue. Site Noise and impact on receivers. Every Tx has side band noise. Carrier impact on Blocking and Selectivity. Blocking can occur crossband e.g. FM Broadcast into UHF Trunking Intermodulation Analysis (dbs FAIM LT 2014 and F-Intermod) 47
Thank You