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Introduction

This document describes the ability of the InfiNet devices ability to provide sustainable wireless connectivity with mobile objects in various scenarios. There is a basic project presented genarally and the features of its implementation for the  A basic deployment is generally presented along with the features related to its implementation for the mining industry, railway and water transport.

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Basic requirements

Let's look at the basic scenario below (Figure 1), which involves the movement of one or more objects throughout the enterprise area along a given path between points A and B. The network control center is located at a certain distance from the area there where the moving object can be located.

The project goal is to organize a reliable wireless connectivity between the control center and the mobile objects in order to provide various information services, such as telemetry data gathering, video surveillance, telephony , etc.

Two categories of tasks must be solved to achieve this goal:

1. Network establishmentNetwork deployment including the following sections:
   • A backbone backhaul radio network creation. The coverage of the backbone backhaul radio network should correspond to the object movement 's area of motion.
   • An aggregation node creation. The aggregation node is designed to join the backbone to collect the traffic of the backhaul radio network devices and is it is a gateway between the radio network and the enterprise network.
   • To establish a backbone A backbone link between the aggregation unit node and the control center.
2. Fault tolerance and roaming providingcapabilities for:
   • Ensuring the link fault tolerance at the access level (backhauling).
   • Providing seamless subscriber roaming within the backbone backhaul radio network.
   • Ensuring fault tolerance of the main link between the aggregation unit and node and the control center.
   • Ensure the possibility of QoS policy implementationEnsuring the possibility of implementing QoS policies.

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Solution

Network

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deployment

The solution of the network establishing problems solution to the tasks described above is shown in Figure 2 . The solution can and it can be divided into four components:

• An enterprise network.
• An aggregation node.
• A backbone radio network.
• Object movement area.

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• The backbone link towards the enterprise network
• The aggregation node
• A backhaul radio network
• The object's area of motion

The backhaul radio network consists of several base stations (BS) joined , joined by a wired infrastructure. Each BS can consist of one or several sectors , the and the combination of their antenna patterns forms the radio network coverage area. As CPEs and BS sectors, the InfiMAN 2x2 family  The InfiMAN 2x2, InfiMAN Evolution families devices can be used as CPEs and BS sectors. Keep in mind that wireless links as well as combined infrastructure can be used to join several BSs.

The base stations are joined by joined at the aggregation node where the node where the InfiMUX switch device is installed. As shown below, the InfiMUX simplifies the configuration of InfiNet devices by adding all BSs configuration for the InfiNet devices by joining all the BSs into a single MINT area.

A backbone link is established between the aggregation node and the network control center. The choice of channel-forming devices is specific devices for the radio link is determined by the transmitted traffic capacity (see Performance of the InfiNet Wireless devices) the following throughput values can be achieved:

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see Performance of the Infinet Wireless devices).  The following throughput values can be achieved:

• InfiLINK 2x2 family devices: up to 280 Mbps.
• InfiLINK Evolution family devices: up to 670 Mbps.
• Quanta 5 and Quanta 6 families devices: up to 650 Mbps.
• Quanta 70 family devices: up to 480 Mbps.
• InfiLINK XG family devices: upto 500 up to 500 Mbps.
• InfiLINK XG 1000 family devices: upto 1000 up to 1000 Mbps.

One subscriber A subscriber station (CPE) is installed on each mobile object , the and its configuration contains radio profiles for each BS sector in its area of motion. The operation operational principle is that the CPE can switch the connections while moving between BSthe base stations. Since the BS sectors provide coverage for the entire area in which the CPE can be located, the CPE is always in the coverage area of at least one BS. As soon as the radio parameters of the current connection deteriorate, the CPE breaks CPE interrupts the radio link and connect connects to another sector. So, while the object moving moves from point A to point B (Figure 2) the CPE is connecting one by one to the sectors of BS1, BS2, BS3 and BS4.

Keep in mind that the CPE cannot be simultaneously connected to two BSbase stations, because the device has one radio module, so CPE switching between the BSs is so the roaming between the base station sectors is accompanied by a short-term connectivity break. Several CPEs can be simultaneously connected to one BS sector.

Fault tolerance and roaming

In addition to the infrastructure described earlier there is extended an extended list of tasksrequirements, which makes make the solution fault-tolerant and more efficient:

• The link fault tolerance at the access level is ensured by overlapping the sectors' radiation patterns on patterns at the backbone backhaul radio network designing design stage. So, if there is an overlap with neighboring sectors more than 50% overlapping with the neighboring sectors, a failure in one of the sector failure sectors will not affect the coverage area of the radio network. Radio frequency planning requires a complex approach and it is discussed in more detaily detail in the following sections.
• As noted, roaming in the proposed solution is not seamless, because CPE switching between different BS is because the roaming between different base stations is accompanied by a connectivity break. A seamless roaming requires an requires the installation of a second CPE device on each moving object. Such a solution is detaily described below.
• InfiNet devices can be used in various scenarios of point-to-point links link reservation and aggregation. For example, the backbone link can be reserved using the proprietary failover technology which requires an requires the installation of a second backup wireless devices setlink. Failover allows automatic reservation of the backbone link using only one frequency channel. Options The options for organizing link reservations reservation are presented in the Link aggregation, balancing and redundancy document.

An implementation The implementation of a QoS policy does not require the installation of additional devices installation and it is solved by configuring the wireless devices units and the InfiMUX configurationdevice:

• The telemetry gathering service, telephony and the remote control are sensitive to delay and jitter, so they require careful configuration of traffic distribution rules by classes. Low A low jitter for sensitive services can be achieved by using software versions with TDMA technology support on the InfiMAN 2x2 and InfiMAN Evolution devices. A comparative analysis of between the Polling and TDMA multiple access technologies is provided in the TDMA and Polling: Application features document.
• The video surveillance service, in addition to the delay requirements, requires the demands an increased throughput in the uplink (from the CPE to the BS). The InfiMAN 2x2 devices family supports and InfiMAN Evolution devices families support the time division multiple access method (TDMA), which allows an administrator flexibly allocate a flexible allocation of the available throughput between the upstream and downstream channels.
• Using a single infrastructure to provide a range of different services requires flexible allocation of available the available throughput between them..

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radio_planning radio_planning

Radio planning

Each the considered solution implementation is Each implemented solution is unique and requires careful preliminary planning. It is a very important stage, saving resources at the design stage can greatly increase operating the operational costs. Within this document, the radio frequency planning issues and devices placement will of the devices will be reviewed.

RF planning

Frequency planning is a complex, creative process that defines:

1. Installation The installation coordinates.
2. Suspension The suspension height, azimuth and antenna elevation.
3. Devices partnumbersThe part numbers of the devices.
4. Frequency The frequency channels and the transmission power.

The result of the frequency planning is a device allocation map with basic radio settings. A convenient tool for radio planning and potential performance assessment depending on the radio parameters is InfiPLANNER.

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1. Regulatory restrictions: RF regulation is determined at the legislative level. Usually, a frequency range  it is allocated either a frequency range that is allowed for free use with certain restrictions(radiated power, antenna suspension height , etc.) , and or a frequency range for which the permission must be obtained.
2. Radio module capabilities: the wireless device radio module supports of the wireless devices supports a limited set of emitted emission frequencies , this and this should be taken into account at the designing design stage.
3. Physical features of the electromagnetic waves propagation: propagation distance, the effect of precipitation and interaction with obstacles are determined by the electromagnetic wave frequency, which must be keep kept in mind during preliminary calculations. The radio waves propagation effects are detaily described are detailed in the Wireless Networking Fundamentals online course.
4. The interference level: the operation of third-party wireless devices has a significant impact on the system's performance, take so it should be taken into account when designing the link. The interference level is affected by the radiation radiated power and the  frequency channels used on thirdby the frequency channels used by the third-party devices operating in the areasame area. In addition to interference from third-party devices, the neighboring sectors can have influence on each other. Reducing interference from  The reducing of the interference between your own devices can be achieved by using different frequency channels. Recommendations for frequency diversity are given in the TDMA and Polling: Application features document. Particular attention should be paid to the frequency channels channel selection in projects with multisectoral multisector configurations in order to minimize the influence of the BS sectors on each other.

The frequency distribution Some frequency allocation examples are presented below. Figure 3a illustrates a scheme there where each BS sector has it's own frequency channel. This approach requires the allocation of 4 frequency channels.

Let's look at the optimized scheme (Figure 3b). Since the sectors' position is chosen in such a way that the radiation patterns of BS1 and BS3, BS2 and BS4 do not intersect in pairs, they will not interfere with each other. This will optimize the frequency resource usedutilization, reducing the number of frequency channels from 4 to 2.

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Device allocation

The device position in The position of the devices in space determines the actual quality indicators of the wireless link. The position of the device devices is determined by the:

1. Installation coordinates.
2. Azimuth and antenna elevation.
3. Suspension height.

In projects with mobile objects, the antennas antenna's directional properties should be taken into account. If the BSs are static and the radio coverage area is constant, then the CPEs CPE's antenna radiation pattern can greatly affect the link quality. InfiNet's product portfolio includes devices with integrated antennas and the ability to connect external antennas , the device selection is determined by the project specificsas well. The selection of a specific device is determined by the specific requirements of the project.

The route profile must be evaluated along the entire trajectory of the object trajectory. This will allow to find potential "dead zones" there will be no connection , with no connectivity with the mobile object and . A decision to change the location of the BS if necessaryseveral base stations might be necessary in this case. In addition, perform a survey on enterprise the survey along the enterprise's territory, because the InfiPLANNER link planning tool does not take into account the effects of obstacles such as trees, buildings , etc.

The InfiNet product portfolio includes a wide range of accessories, including mounting kits that allow to install devices in various conditions with the possibility of flexible alignment , and the CAB-RV1 alignment tool which allows to perform preliminary device diagnostics.

The MINT protocol

The Ethernet link layer protocol was developed for wired the wired networks and does not take into account the specifics of the wireless environment. Wireless device manufacturers can use standard wireless protocols, such as Wi-Fi, or use their own developmentsself-developed protocols. InfiNet Wireless company is developing has developed a proprietary data transfer protocol called MINT designed , especially designed for data exchange in a wireless environment.

MINT (Mesh Interconnection Network Technolohy) -  InfiNetInfiNet's proprietary technology used in by the InfiLINK 2x2, InfiMAN 2x2, InfiLINK Evolution and InfiMAN 2x2 Evolution family devices, provides data transfer between devices via wireless and wired links.

MINT area

One of the MINT protocol's main concepts is the MINT area. A MINT area consist of many neighboring devices , data and data exchange between them is carried out using MINT frames (see check the "MINT protocol" lesson of the InfiLINK 2x2 and InfiMAN 2x2: Switching online course).

Let's look at the solution described above applying MINT described below, that implements the MINT areas concept (see Figure 4). A radio link is installed between the Master and Slave devices, they form the MINT 5 area. Each of the BS1, BS2, BS3, and BS4 sectors is potentially ready to establish a radio link with the CPE installed on the mobile object , forms and form a separate MINT area with the corresponding identifier.

Note that the MINT protocol is intended for data exchange within the MINT area. Data outside the MINT area can be transmitted using other channel protocols, such as Ethernet, i.e. CPE the CPEs and each of the base stations are the BS sectors is the gateway between the MINT and Ethernet networks. In the our scheme, data is exchanged between a mobile object and a control center, i.e. the frame will go through several Ethernet segments and MINT areas in the forward and backward directions. Thus, switch groups group configuration on each device is a prerequisite for data transfer:

switch group 1 add eth0 rf5.0
switch group 1 start
switch start

In addition to Ethernet frames encapsulation during transmission encapsulating the Ethernet frames during the transmission through the MINT area, the MINT protocol performs an exchange of service messages to fill in the frame redirection table. The frame redirection table allows to select the frame transmission route (see video 5) through the MINT area in accordance with the radio parameters and the link load. This mechanism guarantees the selection of the route with the optimal radio parameters and prevents loops.

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If necessary, you can influence the path selection algorithm by setting the link metrics metric value manually.  This This can be done by summing the calculated and additional costs or by fixing a certain value (switching in InfiNet Infinet devices is detaily described in the online course InfiLINK 2x2 and InfiMAN 2x2: Switching)

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Data transfer and QoS configuration on each wireless devices device is a time-consuming task that can be simplified by expanding extending the MINT area.  Schemes The schemes intended to reduce the wireless devices configuration by combining simplify the configuration of the wireless devices by joining them into a single MINT area, are shown below.

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unified_mint_mux unified_mint_mux

Joining sectors into one MINT area using InfiMUX

The main disadvantage of the solution above is a necessary switch groups configuration is the necessity to configure switch groups on all wireless devices. Since the switch group is a gateway between MINT and Ethernet, it is possible to combine all the BSs of the radio network into a single MINT area by assigning , transferring the gateway function role to the InfiMUX switch (see Figure 5). In this case, the  a switch group is need has to be configured only on the InfiMUX. Joining devices into a single MINT area and the advantages of such a scheme are described in the InfiLINK 2x2 and InfiMAN 2x2: Switching online course.

Using the MINT protocol in a wired infrastructure is possible with the help of the PRF (pseudo radio) interface. It is a virtual interface that has a wired interface as a parent and encapsulates MINT frames in Ethernet framesit encapsulates Ethernet frames into MINT frames. Configuration via CLI:

• Create a PRF interface on a wireless device or InfiMUXon the InfiMUX:

  Code Block
  language text theme Emacs title Create PRF interface
  ifc prf0 mtu 1500 up prf 0 parent eth0 hwmtu 1514 mint prf0 start

• Join RF and PRF interfaces on the wureless wireless device:

  Code Block
  language text theme Emacs title RF and PRF interfaces joining
  mint join rf5.0 prf0

• Join two PRF interfaces on InfiMUXthe InfiMUX:

  Code Block
  language text theme Emacs title Two PRF interfaces joining
  mint join prf0 prf1

The advantages of such a solution is the simplification of the QoS configuration, as traffic processing rules for different service classes  are configured only on the InfiMUX.

Joining sectors and the backbone link

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into one MINT area

The disadvantage of the scheme with backbone having the backhaul radio network devices joining in joined into a single MINT area is the quality of service policy complicationof service policy that needs to be implemented at the backbone devices as well: the used traffic classification rules must be duplicated on the InfiMUX and on the Master and Slave devices. If these rules are not duplicated, the effect of the QoS policy implementation can be significantly reduced.

One of the solutions is to combine the channel-forming devices of the backbone link into a single area with all the other devices (see Figure 6).  This This solution is realizable possible only when using InfiLINK 2x2 family devices on or InfiLINK Evolition families devices for the backbone link.  In In this case, the unified traffic classification rules configured on the Master device will be valid in the entire MINT area. In addition, the gateway functions between MINT and Ethernet can be transferred to the Master device, while any switch can be used instead of InfiMUX. Areas joining is carried out similar way as the above configuration. 

Roaming

The movement of the mobile object, with the CPE installed on top, within  within the backbone access radio network is accompanied by a transition from the coverage area of one BS sector to another sector's coverage area of the same or of another BS. The CPE transition process of the CPE between BS the BS sectors is called roaming. Roaming is accompanied with radio link brake Roaming implies the disconnection of the radio link with the first sector and the connection establishment with the second sector.

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1. There is a radio link between the CPE and BS1.
2. The vehicle moves and the radio link between CPE and BS1 breaksbecomes unavailable. The reason is the inability to maintain the communication due to insufficient signal energypower. As it is shown below, the breakage initiator of the radio link can be both CPE and disconnection can be either the CPE or the corresponding sector BS1of BS1.
3. The CPE is trying to reconnect to BS1. If successful, the algorithm returns to step 1; if not - to step 4.
4. The CPE searches for devices to establish the radio connection.
5. The CPE finds out BS2 and tries to establish a connection with it.
6. The CPE establishes a radio link with BS2.

Radio link

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establishment

A radio link can be established between two devices if the following requirements are met:

• At least one device of the devices has a Master role. Possible connections: Master-Master, Master-Slave. The solution architecture suppose configuration architecture implies the configuration of the BS sectors as Masters , and of the CPEs as slavesSlaves.
• A radio profile has been created in CPE the CPE configuration, corresponding to the radio settings on the settings of  the BS.
• Signal The signal parameters (RSSI, SNR, etc.) allow data the data exchange at least at the minimal modulation.

Radio profiles

On Master devices, only one set of radio parameters can be configured, which will be used to establish the links. On Slave devices, several radio profiles can be created, or only one with , but with the ability to automatically select a frequency. Configuration via CLI:

• Configure the radio parameters on the Master device:

  Code Block
  language text theme Emacs title Frequency configuration on the Master
  rf rf5.0 band 20 rf rf5.0 mimo greenfield rf rf5.0 freq 5510 bitr 130000 sid 10101010 burst rf rf5.0 txpwr auto pwrctl distance auto

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• Create a radio profile on the Slave device with automatic frequency selection (if a profile with a fixed frequency value is used, the command below will not be executed):

  Code Block
  language text theme Emacs title Radio profile with automatic frequency selection
  mint rf5.0 prof 1 -band 20 -freq auto -sid 10101010 \ -nodeid 60755 -type slave \ -autobitr -mimo greenfield

When the Slave device tries to establish a connection, it cyclicaly look looks over the radio profiles added to its configuration. As soon as one of the profiles became becomes suitable for a link establishment with the master Master device, starts it initiates the connection and the profile search is stopped. In case that a profile with automatic frequency selection is createdused, the Slave device tries to establish a connection with the Master by searching through the frequencies supported by the radio module. The list of frequencies to search through may be limited by the configuration of the user frequency grid.

Example of a custom frequency grid configuration via CLI (for the rf5.0 interface, the frequency range from 5000 MHz to 5100 MHz with a step of 10 MHz is set, which can be used as the center link frequency with when using a channel width of 20 MHz):

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Obviously, link establishing can be a longtime operation when the automatic frequency selection mode is used due to the wide range of frequencies supported by the radio module. It is unacceptable in scenarios with roaming, therefore, we recommend to create create on the CPE separate radio profiles for each BS sector of the backbone backhauling radio network in CPE configuration.

Dynamic frequency selection

Master devices same as well as a Slave devices, support the dynamic frequency selection (DFS) mode. Devices with DFS support, before  Before selecting a frequency, scan the devices with DFS support scan the available frequency channelsrange, evaluate the interference level and the radars presence of radar. Operation  The operational channel is selected among the frequency channels free of radar, with  having a minimum interference level.

DFS is a standard technology for wireless devices, but the disadvantage is that the assessment of the radio environment is performed only at the start and is not updated during only in the beginning and no updates are performed during operation. Using an additional radio module, on some models of InfiNet devices, allows to implement the proprietary Instant DFS technology. An additional radio module constantly scans the air, performing a transition a swap between frequency channels in accordance with the interference level. DFSlevels in real time. The DFS, Radar detection , and Instant DFS technologies are detaily described in the Dynamic Frequency Selection document.

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• Enable DFS on the Master device:

  Code Block
  language text theme Emacs title DFS enable
  dfs rf5.0 dfsonly dfs rf5.0 freq auto

• Enable DFS and Radar detection on the Master device:

  Code Block
  language text theme Emacs title DFS and Radar detection enable
  dfs rf5.0 dfsradar dfs rf5.0 freq auto

• Enable iDFS Enable the iDFS support on the Master and Slave devices:

  Code Block
  language text theme Emacs title iDFS enable
  mint rf5.0 -idfs

Frequency roaming

In this document frequency roaming is a change roaming represents a change in the operating frequency of the link operating frequency, i.e. the frequency change is performed on both devices.

The frequency roaming mechanism operation is closely related to the Instant DFS function, when frequency channels . When a frequency channel with a lower interference level is detected, the BS sector in PtMP mode or the Master in PtP mode must change the operating frequency. At the same time, the devices connected to them must also change the frequency channel. The devices behavior during  The behavior during frequency roaming is determined by the "roaming" parameter value:

• leader: the device set sets a new frequency channel and sends service messages to other devices to change the their operating frequency as well. We recommend to configure this function on a device with the DFS / iDFS function enabled.
• enable: the device, having received a command to change the operating frequency from the "leader", performs the transition to a new frequency channel.
• disable: the device, having received a command to change the operating frequency from the "leader", ignores it.

This solution does not use the DFS technology, however, in projects where the use of DFS / iDFS is necessary, it is advisable to configure the BS sectors as "roaming leader" , and CPE the CPEs as "roaming enable".

Configuration via CLI:

• Enable roaming on the Master device:

  Code Block
  language text theme Emacs title BS sector configuration
  mint rf5.0 roaming leader

• Enable roaming on the Slave device:

  Code Block
  language text theme Emacs title CPE configuration
  mint rf5.0 roaming enable

• Restart the rf5.0 interface on both devices

  Code Block
  language text theme Emacs title BS and CPE configuration
  mint rf5.0 restart

Note that a Slave device with "roaming enable", having received a command to change the operating frequency from the "roaming leader", will switch to another frequency channel even if there is no corresponding radio profile in the Slave device configuration. In this case, after a reboot, the slave will not be able to establish a link, because it will still be guided by a by the set of radio profiles added to the configuration.

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 The MultiBS function

The main disadvantage of the roaming mechanism is that CPE, after breaking the link with BS1, tries to restore this connection and, only after several unsuccessful attempts, searches : The CPE tries to keep the connection with BS1 until the signal is completely lost, and only then starts searching for other BSs to establish the a new connection. InfiNet  Infinet devices support the proprietary MultiBS function, which speed speeds up this process.

The roaming mechanism with the MultiBS function is presented below (see video 3):

1. Link The link is established between BS1 and the CPE.
2. The vehicle moves and the radio link parameters between the CPE and BS1 deteriorate. CPE breaks  The CPE interrupts the connection with BS1. Despite the fact that the radio link between the CPE and BS1 can be used to transmit data, CPE notice the CPE notices a negative trend and preventively breaks the connection.
3. The CPE searches for devices to establish a connection.
4. CPE finds out The CPE senses one of the BS2 sectors and on BS2 and tries to establish a link with this device.
5. The CPE establishes a radio link with one of the BS2 sectors.
   
   

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Run the following command to enable the MultiBS function:

mint rf5.0 roaming enable multiBS

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The global function

Let's look at the at a scenario in which the cable route the wired connection between the InfiMUX and the BS1 and the power injector was of BS1 is damaged (see Figure 7), i.e. power is supplied to BS1 and the device is ready to establish radio connections, but data can not be transmitted to the control center.

The vehicle with the CPE starts installed starts moving along the trajectory, from point A to point B. Being in the BS1 coverage area CPE , the CPE establishes a radio link with it. Since the cable route is the wired connection is damaged, no data is transmitted between the moving object and the control center. Moving along the trajectory, the mobile object get gets in the area when where it is possible to connect to BS2, but the connection parameters with BS1 are satisfactory and the CPE does not perform roaming between the BSBSs. Without the configured MultiBS function, the CPE will keep the connection with the BS1 sector until it leaves its radio coverage area.

The "Global" proprietary feature avoids this situation. If the Global function is activated on CPEthe CPE, then CPE  it will establish only establish a radio link only with devices there the devices on which the Global function is also enabled. In addition, devices in the same MINT area can perform a proxy function for devices with the Global function enabled. Thus, if the Global function is enabled on the InfiMUX and on the CPE, then all the BSs will inform the CPE that they have a connection to with the InfiMUX with the Global function activated at the time the radio connection is established. If a cable route is a wired connection is damaged between BS1 and the InfiMUX, BS1 will not inform the CPE about the availability of the InfiMUX, i.e. the speaker the CPE will not establish a radio link with BS1.

Using the Global function allows to increase the fault tolerance of the backbone backhaul radio network, however, it will have an effect a positive effect only with an appropriate radio frequency planning - planning since the coverage areas of the sectors must be overlappedoverlap.

Device configuration via CLI:

• Enable the Global function on the CPE:

  Code Block
  language text theme Emacs title Global function on CPE
  mint rf5.0 roaming enable global

• Enable the Global function on InfiMUXon the InfiMUX:

  Code Block
  language text theme Emacs title Global function on InfiMUX
  mint prf0 roaming enable global

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Link establishment process control

One of the mechanisms determining the mechanisms to determine the moment of disconnection from one sector and establishing connection and the establishment of a connection with another, is the assessment SNR of the SNR threshold values threshold. Two thresholds are used in a wireless device configuration:

• hiamp: minimum SNR value required to establish a radio link between two devices.
• loamp: minimum SNR value at which the radio link between devices will not be broken.

Thus, threshold the thresholds values' configuration on a on the BS or CPE on the CPE is the mechanisms mechanism for controlling the roaming process of CPE roaming.

The SNR level configuration for establishing a radio link on wireless devices is performed using the following commands:

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mint rf5.0 -loamp 0

Fixed/mobile/nomadic modes

One of the factors affecting the link parameters with for a moving object is the relevance of the MINT frame redirection table. This The below configuration can only be applied on the InfiLINK 2x2, InfiMAN 2x2, InfiLINK Evolution and InfiMAN 2x2 Evolution families devices. Device The device configuration allows to set the update interval for the MINT redirection table entries by choosing one of the three "mode" parameter values:

• fixed: the redirection table is updated at intervals of 3 seconds. This mode is intended for the static link organizationstatic (fixed) links.
• nomadic: the redirection table is updated at intervals of 1,5 seconds. This mode is intended for the link organization with slowly links connecting slowly moving objects.
• mobile: the redirection table is updated at intervals of 1 second. This mode is intended for the link organization with mobile connecting mobile objects.

As shown above, a CPE with activated the MultiBS function compares activated, compares the current radio link performance with the maximum achieved. There is a possible scenario in which the radio link parameters deteriorate sharply due to the short-term influence of the interference and also recover recovers sharply afterwards. The CPE will break the connection with the BS in accordance with the MultiBS function algorithm, despite the fact that the radio link parameters deterioration had a short-term natureoccurrence. The “mode” parameter selection affects the radio parameters' analysis when the MultiBS function is enabled, by setting the evaluation time interval. Thus, a device in a fixed mode evaluates the radio parameters over an a three seconds interval and is it is more resistant to link rupture link disconnection under short-term interference, than a device in a mobile mode., that evaluates the parameters more often.

Mode parameter in the device The "mode" parameter can be configured by using the following commands:

• Set the fixed mode on the Master and Slave devices:

  Code Block
  language text theme Emacs title Fixed mode configuration
  mint rf5.0 -mode fixed

• Set the nomadic mode on the Master and Slave devices:

  Code Block
  language text theme Emacs title Конфигурация режима nomadicNomadic mode configuration
  mint rf5.0 -mode nomadic

• Set the mobile mode on the Master and Slave devices:

  Code Block
  language text theme Emacs title Конфигурация режима mobileMobile mode configuration
  mint rf5.0 -mode mobile

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two_abonent two_abonent

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Seamless roaming

As shown above, the MultiBS function speeds up the CPE roaming between the BSs, however, in any case, roaming is still accompanied by a short break in the connection. Link interruption avoidance can be reached be achieved by using two CPEs on a on the moving object, combined by with the functionalities of the InfiMUX. In this case, each CPE will independently establish a radio link with the BS , and InfiMUX will distribute data traffic between those and the InfiMUX will route the data traffic by choosing one of those links.

Let's look at the roaming algorithm with two CPEs (see Figure 8):

1. CPE1 and CPE2 have established links with the BS. In this case, no loop appears loop occurs because all radio devices are joined in one MINT area and devices the devices use a frame redirection table that takes into account the cost parameters.
2. The vehicle is moving, CPE2 breaks the link with BS1. CPE1 keeps the connection with BS1. Service  The service hasn't been interrupted, because the data exchange between the vehicle and the control center is carried out via the CPE1-BS1 link.
3. CPE2 is looking for for a BS to establish a radio link. CPE1 keeps the connection with BS1.
4. CPE2 establishes connection with BS2. CPE1 keeps the connection with BS1. When transmitting data, the InfiMUX uses one of the two links CPE1-BS1 and BS1 or CPE2-BS2, with a lower metric.
5. The vehicle is moving, CPE1 breaks the link with BS1. CPE2 keeps the connection with BS2. Data  The data transmission is performed via the CPE2-BS2 , link , service and the service hasn't been interrupted.

To make configurationTo perform the configuration, PRF interfaces should be created on the CPE1 and CPE2 devices towards InfiMUX, and on InfiMUX - PRF interfaces towards the InfiMUX. PRF interfaces should also be created on the InfiMUX towards the wireless devices. In addition, the switch groups configuration must be performed on the InfiMUX, not on the CPEs.

...

config save

Additional materials

Online courses

1. Wireless Networking Fundamentals.
2. InfiPLANNER: Link Planning Tool.
   
3. InfiLINK 2x2 and InfiMAN 2x2: Switching.
   

White papers

1. Performance of the InfiNet Wireless devices.
   
2. Link aggregation, balancing and redundancy.
   
3. TDMA and Polling: Application features
   
4. Dynamic Frequency Selection.
   

Webinars

1. InfiNet Infinet Wireless equipment installation, grounding and lightning protection.
   
2. Switching configuration using InfiNet Infinet Wireless devices - typical scenarios.
3. InfiNet Infinet Wireless PtMP network design with frequency reuse and SYNC.
   

Others

1. InfiNet Wireless products.
2. Link planner tool InfiPLANNER.