Tips and Tricks for Operators
This page provides an archive, alongside our forum, of the tips and tricks collected by our Director of WISP Markets, Rick Harnish. These are categorized chronologically with the latest BaiTips appearing at the top of the page.
As always, if you have any questions please contact firstname.lastname@example.org for assistance.
Using CloudKey to add UEs to your CloudCore Account
July 20, 2017
With recent upgrades to the Operators Management Console (OMC) and UE firmware version BCE-ODU-1.0.8, comes a new simple way to add your UE devices to your CloudCore account.
When an operator logs into their CloudCore account, they will see their CloudKey in the top right hand corner of the screen. This key is unique to every operator’s account. See the image below. The CloudKey for Fisci has been marked out with red pen.
Once a UE has been upgraded to BCE-ODU-1.0.8, the web GUI will allow the operator to insert this CloudKey into the UE and it will automatically add the UE to the Device Manager. Below is an image that shows where this field is located. It is highlighted in yellow. In the UE web GUI, go to System/TR069 and enter the Cloudkey from top right corner on OMC. Click submit and in a few minutes, once the UEattaches to the eNodeB, it will appear in CPE monitor on OMC. Reboot is not required for this field to take effect.
This is a duplicate method of adding a UE to the OMC. The other way is to use the Device Manager. This method is found by logging into your OMC account, click on System/Device Management and click +Add in the top right corner. A field will appear to insert the UE MAC address. Fill it in and the UE device will be added to your account.
Either method works. So if the installer did not write down the MAC address, you can still login to the UE, remotely or directly, and add the CloudKey.
How to Modify and Assign A Service Plan in the BOSS
March 31, 2017
Operators using the Nova R9 eNodeB firmware versions BaiStation_V100R001C00B100SPC005S and later, now have the ability to set up service plans to throttle the upload and download bandwidth of the clients. Below are the steps to set up and assign service plans to the subscribers using the BOSS.
1. Add a new service plan as shown in the figure below:
2. Enable the new service plan added as shown in the figure below:
3. Search for the subscriber for which the new service plan will be applied, and click “Detail”:
4. Change New Service of the specified subscriber to the new service plan and click “Save”:
After finishing this step the specific subscriber will have the new service plan applied upon them.
Don’t Use Legacy LMR Cable with LTE, Go Low-PIM!
March 21, 2017
LMR cable has been a staple to the fixed wireless industry for years, but with LTE we recommend that operators use Low-PIM instead.
PIM stands for Passive Intermodulation and is defined as the unwanted signals generated by the non-linear mixing of 2 or more frequencies.
This translates as high PIM resulting in poor reception and limited bandwidth to the end user, while low PIM results in strong signals and more bandwidth for end users. From a hardware perspective, this means that each and every connection must be designed to minimize PIM and tested to ensure it is installed properly.
Extensive testing by LTE providers discovered that legacy LMR braided cables may test perfectly in a Return Loss or VSWR test, but generally possess only average PIM performance. The braided outer conductor can act like hundreds of loose connections that behave poorly when tested for PIM, particularly as they age. For permanent installations, braided cables are not recommended. Times Microwave has recently introduced the LMR-SW Low-PIM cable to the market.
PIM lowers the reliability, capacity and data rate of LTE systems. It does this by limiting the receive sensitivity. As LTE usage grows, licensed and unlicensed spectrum has become crowded. Engineers must often select less desirable RF carrier frequencies and accept potential PIM issues. Compounding this problem, existing antenna systems and infrastructure are aging, making any PIM that does occur stronger.
When PIM interference falls within the receive band of a LTE base station, it makes the receiver less sensitive to weak signals that limits receive coverage. This increases the block-error-rate (BLER = No of erroneous blocks / Total no of Received Blocks. Normal BLER is 2% for an in-sync condition and 10% for an out-of-sync condition). If the connection is for data, interference from PIM creates more error protection bits and resends, which causes a lower overall data rate. In some cases, PIM can even cause receiver blocking, shutting down the sector.
PIM shows up as a set of unwanted signals created by loose or corroded connectors, nearby rust, medium or high PIM braided cable products and other variables listed below. Other names for PIM include the diode effect and the rusty bolt effect.
Some of the more common components that can cause PIM include:
Connectors on the antenna run are the first suspects in any PIM hunt. Connectors are a likely cause of PIM and subject to a number of problems. First, if the mating surfaces have small gaps, a “voltage potential barrier” can be formed that allows electron tunneling (a diode effect) or microscopic arcing to take place. Either will cause PIM in the presence of strong signals.
Damage caused by over-tightening, insufficient contact pressure, distorted contact surfaces, foreign material in the mating surfaces, or corrosion can cause small gaps. In addition, corrosion may create crystals, which also have a nonlinear effect on RF signals. Corrosion is a particular problem in coastal areas where humidity and salt air are prevalent. In this case, connectors may need cleaning on a regular basis.
While it’s not a common problem with connectors designed for LTE service, it is worth mentioning that manufacturers make low PIM connectors with nonferrous materials. Ferrous materials have a nonlinear effect when used with RF signals. For example, stainless steel can add 10 to 20 dB of PIM to the signal.
Connectors with nickel plating, or gold over nickel, can add 20 to 40 dB of PIM to the signal. Connectors made for LTE usage are non-ferrous and plated with coatings such as silver, white bronze, and gold.
Cutting the cable at installation time may create metal particles or debris. If some of these particles remain in the cable, or get into the finished connector, they can cause PIM when they touch a current carrying surface. Contaminates can be a source of intermittent PIM if the cable assembly is flexing with temperature or from the wind.
The center conductor depth is important. If it is set too far back, the resulting poor contact may cause PIM under use. If it sticks out too far, it may cause physical damage when connected. This damage may lead to gaps the next time it is connected. One way of dealing with this problem is to use connector-clamping tools that set the center pin depth properly. If pin-depth becomes a common problem, special gauging fixtures are available to measure the center pin depth.
Careful cleaning, proper assembly, good weather wrapping, and proper connector torque are the best solutions to connector caused PIM. Tooling must be kept clean, sharp and well adjusted. Unfortunately, the first instinct when a bad connection is identified is to over tighten the components, which nearly always results in damage by deformation.
Cables do not typically cause PIM, but poorly terminated or damaged cables can and do cause problems. Beware of cables with a seam in the shielding. As the cable ages, this seam can corrode, causing PIM. The cable’s center conductor may also be faulty because plated copper does not always adhere well to the aluminium core. The copper can flake off if poorly manufactured, creating metal particles and poor connections that have the potential to create intermittent PIM.
Cables can change their physical configuration as temperature varies. For instance, sunshine can warm cables, changing their electrical length. A cable that happens to be the right length to cancel out PIM when cool may show strong PIM after changing its length on a warm day, or, it can work the other way around, good when hot and bad when cold. In addition, the physical change in length can make a formerly good connection into a poor one, also generating PIM. Finally, water in the cable run is not beneficial when trying to reduce PIM.
Here are some datasheet links for Low PIM cables from various manufacturers:
Antennas are a critical part of any transmission system. Antennas are subject to fatigue breaks, cold solder joints and corrosion. They take the full power of the signal, or signals, and if they create any PIM, it will be broadcast along with the rest of the signal. If also used for reception, the PIM is already in the conductor, with no transmission loss, ready to cause harm to reception.
Any nearby corrosion can cause PIM. Look for rusty fences, rusty roofs, rusty mast bolts, and so forth.
Keeping rust away from the tower will pay dividends in reliability and let maintenance personnel sleep better at night.
While lightning arrestors do not purposely cause PIM, they are a source of micro arcing. As they age, their breakdown voltage gets lower until finally RF power peaks can cause them to arc in a very similar manner to antenna or connector micro arcs. If one of the connectors becomes damaged, it will cause PIM in the traditional sense. These products have suffered incredible price pressures and are a good example of an item that is not made as well as it once was.
With this information, the smart wireless operator/engineer will use quality Low-PIM components when designing and building their infrastructure. In this competitive RF environment, the smart operator reduces design flaws, construction errors, inspects components on a regular basis and monitors performance on a daily basis to pinpoint when PIM may be secretly rising within the system. These techniques will result in a competitive advantage and will yield happier, better connected customers.
Every dB Counts!
February 24, 2017
Baicells equipment is able to penetrate some nasty foliage, such a dense pine forests in rolling terrain. The following tips can help operators when deploying in difficult scenarios.
- Deploy narrow sectors (65 degree or less) in dense foliage areas to concentrate more RF energy to your client locations.
- Install Low PIM 1/2″ jumper cables to the sectors. Here is a link to an online Coax Attenuation Calculator. Additionally, here is an article about Passive Intermodulation (PIM).
- Use an electronic protractor or inclination phone app to adjust sector down tilt affordably or invest in more expensive equipment to do so. Normally in thick foliage areas, distance will be more limited than open terrain, therefore, sector down tilt can be increased.
- Calculate the UE antenna tilt angle with an online calculator such as http://www.cleavebooks.co.uk/scol/calrtri.htm17. Enter two known values such as tower antenna mounting height and link distance and the calculator will yield the proper tilt angle. Don’t forget to add or subtract elevation changes between the client location and the base of the tower, when entering the vertical side in the online calculator. For example, if the base of the tower is at 850′ and the client location is 700′, with a 200′ mounting height, the proper vertical measurement would be 350′. This information should be given to the installer before leaving for the install. A phone app should be adequate to properly adjust the UE antenna face at the client location. An example image is given below where edge a is tower mounting height plus change in terrain elevation (200′ + 150′ = 350′) and the link distance is 3 miles or 15,840 feet. This installation should have a 1.27 degree up tilt on the UE face.
- Use Google Earth or other application to draw a line between the tower and the client location. This will assist the installer pointing the antenna in the proper direction, shorten installation time and give the customer better performance. It is usually good to provide an image of the entire path and a close up image, to assist with pointing to landmarks and avoiding known obstacles, such as the big trees in the second image below. In this example, moving the UE 20′ to the back of this house, the installer could have avoided shooting into the tree trunks of some very large trees in close proximity. Since the tower was not visible, the installer could not tell. Impress on your installers, Every dB Counts!
- Make sure your installers avoid blocking any portion of the UE antenna face by mounting under eaves or behind pipes or chimneys. Every square inch of the antenna face is valuable real estate to insure Every dB Counts!
Don’t sacrifice performance, Every dB Counts!
Upgrading UE Firmware
January 19, 2017
There have been major enhancements for the Nova eNodeB firmware and the EPC/OMC software, please follow the steps below to ensure you are able to take full advantage of these improvements.
Operators can find and download new firmware releases here.
One important feature to note: Many operators may not be aware of, is the ability to turn on a UEs remote https web login from the BaiOMC. To do this, follow the instructions below:
- Login to the BaiOMC account.
- Go to CPE/Monitor
- Right Click on a UE
- Select Settings
- Click on the Remote Web Tab
- Enable https Login
Once you have access to the UE WebGui, you can proceed to upgrade the firmware. We will also schedule batch upgrades remotely upon request. Please allow up to 48 hours for this to be completed. Email email@example.com if interested.
New Customers BaiOMC: Setting Up an Account
December 19, 2016
The BaiOMC (or CloudCore) is a cloud management console where operators manage, monitor, and onboard new base stations and CPEs. If an operator does not yet have an account, they can go to the CloudCore page, fill out the form at the bottom and click the “Submit” link.
An IPsec tunnel is by default enabled and configured to connect to our cloud EPC. As you may know, an EPC is required for the LTE architecture and as such, we provide a cloud-based EPC to simplify the installation and configuration of new base stations. Essentially, they become plug-and-play with this setup. When the eNodeB has Internet plugged into the WAN port (DHCP client by default) and the base station is powered on, it will automatically connect to the cloud EPC by IPsec and become Active and ready to serve clients.
The CPEs will require SIM cards, which are purchased separately. Before the SIM cards can be used, they must first be added to their operator account and be activated. All new SIM card numbers (IMSI) should be sent to firstname.lastname@example.org with the name of the operator so that we can add the SIM cards to the operator account. Once the SIM cards are added, the operator can activate the SIM cards themselves from CloudCore.
To activate the SIM cards, operators should follow these steps:
1. Log into CloudCore
2. Click “BOSS” at the top left.
3. Click “Subscriber” on the left menu.
4. Click “New” to add a new subscriber.
5. Enter subscriber info and click on the search icon in the SIM card field.
6. Select the respective IMSI number.
7. Click save to add a new subscriber and activate the SIM card.
Physical Cell Identifiers (PCI)
December 15, 2016
When each Baicells eNodeB first connects to the Cloud EPC, it is assigned a PCI number (between 0 – 503). In some cases, this number was the same on several eNodeBs on the same tower. Operators have the ability to change these PCI numbers and should do so. You may want to come up with a plan for these numbers for your deployments, especially as they grow. Larger operators should do some reading on PCI Planning.
The PCI numbers assigned to your eNodeBs should be between 0 and 503. No two eNodeBs in close proximity to another should have the same PCI number. Please check your current deployments and make the appropriate changes. Having two or more common PCI numbers in close proximity may confuse the UEs deployed in the area.
An idea may be to use the same PCI number as the third octet in a private IP subnet you may be assigning to clients off of an eNodeB. For example if PCI = 67, then a subnet might be 192.168 67.0 or 172.16.67.0.
A good article describing the value of proper PCI planning can be found at http://main.rfassurance.com/?q=node/7930
We would also like to thank Anton Kapela for the following summarization of PCI Planning.
Anton Kapela: Let’s start with some assumptions & basic theory of operation here: a) every eNB is frame-synchronized (bits, gps, ptp, sync-e, etc) b) each eNB has been assigned a same ARFCN c) each sector serves roughly the same ‘area’ d) the overall goal is to hold more ‘standing UE’s (ie. each eNB at 32 or less) for the sector heading than one eNB can hold e) users accept a random reduction in MCS rates/achievable bitrates, finally f) we’re running this mac/phy config:
-tdd frame #5, ssf #1
-10 MHz channel bw
-normal cyclic prefix
-2 antenna ports
-PHICH Ng factor of 1/2
-4 PHICH groups, 12 REGs, 32 PHICH resources, and PHICH duration of 1 symbol
This means the first three “best case PCI’s” for us are: 0, 5, and 10 (see images later in thread). This PCI arrangement de-conflicts the important sub-channels of the LTE air frame, but not quite everything, as well read about shortly.
First, a few sub-channels that really, really, really ought not be mutually-stomped upon; that includes the following three items:
-RS (cell-specific Reference Signal), for a given Tx antenna port
-PCFICH (Physical Control Format Indicator Channel)
-PHICH (Physical Hybrid ARQ (Automatic Repeat reQuest) Indicator Channel)
Then there are are three more sub-channels which aren’t effected or steered by PCI selection; those are:
-PSCH (Primary Synchronization Channel)
-SSCH (Secondary Synchronization Channel)
-PBCH (Physical Broadcast Channel)
These sub-channels will forever reside in fixed frequency & time locations on every eNB everywhere; good news, though: their system value isn’t carrying user-related information as much providing basic timekeeping and synchronization of the downlink, and their content is scrambled such that the “pile up” of several eNB isn’t detrimental to a UE’s internal operations.
The only unaccounted parts in our overall airframe of concern, then, are the actual subframe areas that hold the “user data” — that’s the PDSCH (Physical Downlink Shared Channel), which is mapped over all LTE physical resource blocks (PRB), over the entire operating channel bandwidth. An eNB will allocate resources to UE’s on any of the available sub-frame & resource blocks, but it usually starts filling them from sub-frame 0, onwards through sub-frame 9. If we could somehow invert the “fill order” of one eNB (ie. when colocating two or more in a given “sector coverage area”), or even offset its “start filling here” position by some number of subframes, then we’d reduce user-data collisions over the PDSCH even further. This would hold until, of course all of the operating eNB’s were attempting to fully load their PRBs to 100% — it could happen!
Running this out, assuming no special PRB fill order, and assuming there’s some amount of RF isolation through different downtilt (ie. one sector at 0′, one at 3′ or something even more aggressive, with something like 15 to 17 dBi of sector gain, on a ~7′ vertical beamwidth), we’d expect to see HARQ triggered modestly (few %) more often (ie. more incremental-redundancy supplementation due to PRB collisions), and maybe a lower overall MCS rate selection in the DL and probably also the UL, but we wouldn’t expect to see the systems collapse or halt operations. Ideally, the UE’s and the eNB will drive MCS rate selection and transmission mode (TM) selection based on HARQ feedback moment-to-moment–implying that PDSCH collisions should not drag things down beyond short term adaptation windows (ie. tens of seconds). Most systems aim for a packet or “burst” error rate of 8% or less, as this represents less overhead than most large-scale MCS rate steps.
Here’s the first few PRB’s that we care about — demonstrating three PCI ID’s for the config I mentioned earlier having fully-non-conflicting RS, PCFICH, and PHICH allocations.
PCI=0, port=0 — only showing PRB 0 through 7 for clarity here:
December 14, 2016
Operators that would like to squeeze a few more miles/kilometers out of their eNodeB can achieve this by changing the Zero Correlation Zone Config Parameter in the eNodeB Web GUI.
- Log into the eNBs’ web gui.
- LTE Settings->Random Access Parameters page.
- On the Zero Correlation Zone Config parameter, change the default (10) to (12).
- Reboot the eNB
For shorter distances, leave the settings at default. Performance is relative to the CQI, which is based on CINR and Receiver Sensitivity. The CQI defines the Modulation Coding Rate (MCS), which in short distances should be pretty strong unless there are severe attenuating obstacles.
A few operators have experimented with this setting and have achieved good performance at 8 miles/13 kilometers. Theoretical maximum distance is 9 miles/14 kilometers.
A Subframe setting of (2) and a Special Subframe setting of (7) were maintained. It is possible to change the SSF setting to (5) to allow for a longer Round Trip in the Guard Period. Feel free to experiment and let us know your results.
Subframes and Special Subframes
December 14, 2016
This tip is meant to help Baicells customers tweak their LTE settings to better fit their customer needs and demographics. This involves changing Subframe and Special Subframe Assignments.
The Baicells Nova R9 eNodeB operates in TDD mode using the Type 2 LTE Frame Structure. The operator can customize uplink and downlink bandwidth ratios using the Subframe Assignment.
As shown in the top section of the figure below, a LTE radio frame is composed of two half frames, each of 5ms duration resulting in total frame duration of about 10ms. Each radio frame will have total 10 Subframes and each Subframe will have 2 time slots. Subframe configuration is based on Uplink Downlink configuration (0 to 6). Currently, the Nova R9 uplink and downlink ratio assignment options are (1 and 2). Subframe Assignment (1) equals a DL:UL ratio of 2:2, while a Subframe Assignment (2) selection is a DL:UL ratio of 3:1. The default is Subframe Assignment (2) in the Nova R9.
DL to UL configuration number determines what goes in all the Subframes is mentioned below in the table. Usually in all the cases, Subframe #0 and Subframe #5 are always used by downlink. Highlighted in Green below is the default configuration for the Nova R9. As evident in the top graphic, special subframes (SSF) are introduced at subframe1 and subframe 6.
Baicells currently offers two Special SubFrame (SSF) options (5 and 7). The Nova R9 default is 7 (highlighted in green below). The Special Subframe carries a DwPTS (Downlink Pilot Time Slot), a GP (Guard Period) and a UpPTS (Uplink Pilot Time Slot). For the 5ms DL to UL switch point periodicity case, SSF (Special Subframes) exist in both the half frames. For the 10ms DL to UL switch point periodicity case, SSF exists only in first half frame.
Each half-frame of 5 ms carries one Special Subframe that is divided into 3 parts as shown in below figure: DwPTS (Downlink Pilot Time Slot), a GP (Guard Period) and a UpPTS (Uplink Pilot Time Slot). Subframe 0 and DwPTS are reserved for downlink; Subframe 2 and UpPTS are reserved for UL. Remaining fields are dynamically assigned between UL and DL.
This Special Subframe replaces Subframe 1. The individual time duration in OFDM symbols of the Special Subframe parts are adjustable.
- The Guard Period (GP) implements the DL->UL transition point and the GP has to be large enough to cover the propagation delay of DL interferers. Its length determines the maximum supportable cell size.
- DwPTS is considered as a “normal” DL subframe and carries reference signals and control information as well as data for those cases when sufficient duration is configured. It also carries Primary Synchronization Signals (PSS).
- UpPTS is primarily intended for Sounding Reference Signals (SRS) transmission from UE. UpPTS is mainly used for Random Access Procedure (RACH) transmission.
The customer UE always needs a Guard Period in order to switch from receiver to transmitter. The Guard Period includes RTD (Round Trip Delay) as shown in figure below. Thus, if an operator wants to achieve more distance involving a longer Round Trip Delay, a longer Guard Period (GP) may need to be used. In this case, the Special Subframe Assignment should be changed to 5.
If distances over 6 miles/10 kilometers are needed in your deployment. The operator can change the Zero Correlation Zone Config from 10 to 12 by going to LTE Settings->Random Access Parameters in the eNodeB WebGui.
These changes should also improve performance for your longer distance clients. Our theoretical limitations at this time with these changes are 10 miles/16 kilometers. Below are simulation results for Subframe 2 and Special Subframe 7 testing in a lab environment. Actual outside results may be impacted by variables such as wind-blown foliage, interference, backhaul capacity and other attenuating circumstances not normally seen in a lab environment.
Atom UE WAN Interface Access
November 30, 2016
This tip is meant to help Baicells operators use a configuration in the Atom UE/CPE Web GUI to allow HTTPs Login from the WAN interface. By default, the UE firmware blocks access to web GUI from WAN and enabling access will require further configuration.
1) Log into the CPE web GUI, then open the WEB Setting menu (System->WEB Setting).
2) Enable “Allow HTTPs Login from WAN”, then click Submit.
To login to the UE remotely, type the WAN IP address of the eNodeB followed by :5(last four digits of the IMSI number of the SIM card in the UE) into a web browser. In other words, https://X.X.X.X:5xxxx
Baicells Social Media/Forum/Distributors/Resellers
November 28, 2016
We try our best to keep connected with our customers. Feel free to reach out with any questions or opinions that you might have!
Join the BaiCells Community Forum and introduce yourself. Please feel free to create topics and post questions and comments to existing topics!
Other ways to keep up to date with the latest Baicells News can be found at:
1. Baicells Community Forum
2. Baicells Facebook Page
3. Baicells Operators Facebook Group
4. Baicells Twitter
5. Baicells Website
Have support requests, please open a ticket by emailing email@example.com
Pricing information can be found by contacting one of our distributors or resellers here.
CINR Level Comparison Troubleshooting
November 17, 2016
CINR stands for Carrier-to-Interference-and-Noise Ratio. The ratio is between the power of the Radio Frequency (RF) carrier bearing the wanted signal and the total power of interfering signals and thermal noise. CINR levels are expressed in dB. Here is a chart of typical CINR Level ranges:
Excellent: above 22
Good: 16 to 22
Fair: 9 to 16
Poor: below 9
Each RF chain has a CINR result. In the case of 2×2, Baicells expresses the two results as CINR1 and CINR2. These results should be very close together, for example CINR1=20 and CINR2=19. If they are not close together, it would be apparent some sort of attenuation is evident on one RF chain. Therefore, we need to troubleshoot the following items.
- RF path from eNodeB to antenna (water in RF cable, bad lightning protector, bad cable termination, bad cable)
- One radiator in the antenna is defective or disconnected internally (replace with another antenna to test)
- Bad UE (One antenna radiator is defective or disconnected internally or one transmitter is bad. Try another UE)
- RF interference on one RF chain (Try changing to a different frequency)
- Incorrect antenna downtilt or UE antenna is not mounted directly at the eNodeB antenna. (check antenna downtilt and vertical beamwidth in relation to UE location)
- UE mounted outside or at the edge of the eNodeB antenna propagation field. (move UE inside antenna propagation field)
- Bad eNodeB (One RF port is disconnected from the transmitter internally or a bad transmitter. Replace eNodeB)
It is possible to connect a UE with excellent CINR on one chain and less than desirable CINR on the other chain, however the bandwidth capability of the UE may be cut in half. If you are not seeing good bandwidth capacity, always check the CINR levels.
MME and PLMN Settings
November 8, 2016
Operators using the Baicells Cloud Core EPC have two settings in each eNodeB that are mandatory for authentication, the MME = 10.3.0.4 and the PLMN = 31198. Do not change these settings unless you are connecting to a different hardware EPC (core). Below are definitions of MME and PLMN as well as a snapshot of the settings screen in the BiaOMC platform for eNB settings.
MME Mobility Management Entity: LTE Mobility Management Entity is responsible for initiating paging and authentication of the mobile devices.
PLMN Public Land Mobile Network: A public land mobile network is any wireless communications system intended for use by terrestrial subscribers in vehicles or on foot. Such a system can stand alone, but often it is interconnected with a fixed system such as the public switched telephone network.
November 5, 2016
This is a simple chart of current legal frequencies and corresponding EARFCN numbers for the NN 3.65 to 3.70 GHz license. The chart below can be used for both 20 MHz channels and 10 MHz channels to determine the proper EARFCN number.
These are center channels which allow operators to operate legally within the spectrum band. If operating 4 sectors on a tower operating on 20 MHz channels, one would use ABAB configuration with EARFCN 44190 on opposite facing sectors and EARFCN 44490 on the perpendicular facing sectors. This would give 10 MHz of guard band between sectors.
Have an idea for a new BaiTip? Email firstname.lastname@example.org