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1. Product

RAy2 microwave units work as a point-to-point link in a full duplex setting with transfer speeds of up to 360 Mbps. Supported are 2 license-free bands (17 and 24 GHz) and 3 licensed bands (10, 11 and 18 GHz). Bandwidth can be configured from 1.75 up to 56 MHz. Modulation can be fixed or adaptive and can be adjusted from QPSK to 256QAM. RAy2 microwave links operating in 17 and 24 GHz bands can also be operated as a Short Range Device (SRD).

The link is formed by two RAy units, each equipped by its own parabolic antenna and accessories to be fully operational.

RAy2 – Microwave link

Fig. 1.1: RAy2 – Microwave link

RAy product line has been designed to have minimum possible number of hardware variants. Upgrade of functionality does not result in on-site hardware changes except installing a WiFi module – everything else is done by activating software feature keys (see Section 1.6, “Ordering codes” and Chapter 5, Configuration).

HW models are determined only by frequency bands and sub-bands and by a frequency range for RX and TX channels:

  • Licensed bands (10, 11 and 18 GHz) require one RAy unit (labeled L) to transmit in the Lower and receiving in the Upper part of the band. The other unit (labeled U) is operating vice versa. This difference is realized by HW, thus L + U models are necessary for each band (and sub-band). Those units use single polarization only.

  • License-free bands (17 and 24 GHz) are designed differently and both RAy units have identical hardware. Transmitting and receiving channels are freely defined by software and technically separated from each other by cross polarization.
    NOTE: Even all units are hardware identical, default factory settings for each RAy in the pair use different channels for L and U unit (letters L or U are labeled on each unit inside yellow ring below connector flanges), so the link could be established without reconfiguration of radio parameters.

Cross polarization (used only for RAy operating in 17 and 24 GHz bands) means that one side of the link uses one polarization for transmission (e.g. horizontal) and the opposite polarization for receiving (e.g. vertical). The other side of the link is turned by 90°. It therefore transmits and receives using opposite polarization with respect to the other unit. The practical result for users is that RAy2 units for 17 and 24 GHz must be mounted with reverse polarity on both ends of the link.


RAy units for 10, 11 and 18 GHz are all mounted with the same polarization on both ends of the link.

1.1. Antenna interface

RAy2 Microwave link – antenna and RAy unit

Fig. 1.2: RAy2 Microwave link – antenna and RAy unit

RAy2 link requires the use of external parabolic antenna for each RAy unit – both for physical mounting as well as for the wireless transmission itself. Parabolic antennas from different producers are available.

Radio connection between the antenna and RAy unit is ensured by the waveguide on RAy unit (located across the holder), where well lubricated antenna waveguide pivot nicely fits in. The RAy unit is mechanically fixed to the antenna by 4x M8 screws (one per each side of Ray unit). Installation and basic adjustment of the antenna is described in the Section 4.2, “Antenna mounting”. Attaching RAy unit to it by 4x M8x30 (Allen) screws delivered with each antenna or each mount kit is described in the Section 4.3, “RAy unit mounting”. For adjusting the exact antenna direction see Section 4.7.2, “Directing antennas” .


Fifth M8 screw (with standard 6-edge head) delivered with each RAy unit is there to ensure proper grounding of the RAy unit (by a grounding cable), not for mechanical fixing of the unit. This screw is expected to fit one of two M8 thread holes on RAy unit marked by yellow grounding symbol . For details see Section 4.5, “Grounding”.

1.2. Connectors and Interfaces

Each unit is equipped with the following interfaces (on top of antenna waveguide described above):

ETH1+POEGigabit metallic Ethernet port. This port is capable of powering the unit with any Power over Ethernet (PoE) power source working according to IEEE 802.3at standard.
Passive PoE from 40 to 60 V is also supported.
ETH2Slot for user exchangeable SFP module. A wide range of fibre optics Ethernet modules is available. Both single or dual mode transceivers can be used. An SFP module with metallic RJ45 interface can also be used.
The SFP LED (located on SFP, just next to connectors) is controlled by SFP module. Its function is specific for each SFP module. The typical behavior is an indication the received signal from the optical or metallic link to be within operational range.
PDC power connector, from 20 to 60 V.
HW button for service purposes: Internal backup or Factory settings, see Section 5.6.1, “Maintenance”.
SUSB service connector for USB/WiFi or USB/Eth adapters.
RSS voltage output connectors (for example 0.547 V means RSS –54.7 dBm).
Grounding screwFor a proper grounding of the RAy unit – necessary for its function (ensured by galvanic connection to the mast through a grounding cable).

Fig. 1.3: Connectors


Grounding screw has two possible positions (two holes) to be mounted in. Those are located near the left and right fixing screws of the RAy unit and both are marked by a yellow grounding symbol . For more information about unit grounding see Section 4.5, “Grounding”.

A set of all necessary bushing parts are delivered with each RAy unit – see a description of this standard basic accessory SET-RAY2-CON-B. Additional bushing options for installation of longer connectors or other equipment are available as well. For bushings installation see Section 4.4, “Connectors assembly and disassembly”.

All accessories offered by RACOM for proper installation of the complete RAy link setup (including proper grounding) are tested for compatibility with RAy unit. See accessories listed in overview and described in details.


All bushings and plugs (including the original plugs in the flanges) must be fitted with O-rings and carefully tightened. Otherwise, the unit is not protected against moisture intake through connectors and can not offer guaranteed functionality.

1.2.1. RJ45 Ethernet connector ( ETH1+POE )

RJ45 socket connector marked „ETH1+POE“ is a standard 10/100/1000Mbps metallic Ethernet port. One plastic RJ45 plug for CAT5e and CAT6 cables is delivered with each RAy unit, ready to be punched to an Ethernet cable.
NOTE: Higher quality and CAT7 compatible RJ45 plugs are available from RACOM as well – see for example item CON-RJ45-TLG-CAT6.

This port can be optionally used for power sourcing the unit by PoE (Power over Ethernet). Both an active PoE power supply (compliant with at least IEEE 802.3at standard known also as „PoE plus“) and a passive PoE power supply (with voltage range 40-60 V) are supported.

Technical parameters of PoE power input:

  • Supported voltage range is 40 to 60 V, distances up to 100 m. Internal RJ45 pins wiring is :

    • (V+) … 1,2,4,5

    • (V-)  … 3,6,7,8

    It is possible to use all 8 pins or only 4 pins. Use:

    • either   4,5 (V+) and 7,8 (V-)

    • or         1,2 (V+) and 3,6 (V-)

    • or both simultaneously

More information about usage and installation of available power options can be found in Section 4.5, “Grounding” and Section 4.6, “Power supply”.


The microwave unit does not support a combination of both power supplies. Only one power supply – DC or PoE – can be connected at any one time.

1.2.2. SFP slot ( ETH2 )

„ETH2“ is a standard SFP slot for 1000Mbps Ethernet SFP modules, user exchangeable. Both fibre optic and metallic Ethernet SFP modules are supported. For optical both single and dual mode fibre optics Ethernet modules (= 2 or 1 fibers) can be used. CSFP modules are not supported. RACOM offers all mentioned types of SFP modules, tested to be RAy compatible as a standard accessory.

The SFP status LED is located just next to the slot. It is controlled by SFP module. Its function is specific for each SFP module. The typical behavior is an indication the received signal from the fibre optic or metallic link to be within operational range.


It is strongly recommended to use a high quality SFP module. The SFP modules listed in Accessories are thoroughly tested by RACOM and are guaranteed to function with RAy2 units. It is possible to use any other SFP module, but RACOM cannot guarantee they will be completely compatible with RAy2 units.

1.2.3. DC connector + HW button ( P )

Slot „P“ is named according “Power”. It contains a DC power source connector and next to it is located a HW button for service purposes.

Power supply connector

Fig. 1.4: Power supply connector

DC connector (3 pins)

Supported voltage range is 20 to 60 V, polarity is documented on the picture DC connector. RAy internal DC power circuits ensure galvanic separation. Ground pin is connected with the RAy chassis (grounded by Grounding screw to the mast) and it can be used for grounding of DC cable (either positive or negative wire or the shield).

One 3-pin power plug with screw-terminals is delivered with each RAy unit (see SET-RAY2-CON-B), ready to be mounted to a customer DC cable. The connector is designed for electric wires with a cross section up to 1.5 mm2 (AWG 14).

More information about usage and installation of DC power sourcing can be found in section Section 4.6, “Power supply” .


The microwave unit does not support a combination of both power supplies. Only one power supply – DC or PoE – can be connected at any one time.

HW button

It is located in a small hole next to DC connector. It can be pushed by any tiny blunt thing with the diameter up to 2 mm. Its length has to reach about 7 mm in to the hole. (It can be ball pen cartridge – both ends work on the thin one, match, toothpick, etc.).


Usage of very sharp things for pushing the HW button (like needle, edge clip etc.) may destroy the contact inside RAy unit! Such a button destruction is not covered by warranty.

The button supports multiple functions, which are activated dependent on the state of the unit when the button is pushed and the length of the push:

Action to be performedUnit statusButton pushedSYS LED indication
internally temporary stored
customer settings
For 5 secondsFlashes Green
Factory settings

to Local unit, then reboot
Out of powerPushed before power on, released after SYS LED stops flashing redFlashes Red (delayed after power on, for a duration of 5 seconds)
Entering the
Service mode.
(Please, exit this mode
by powering off the unit)
Out of powerPushed before power on, released when SYS LED starts flashing redFlashes Red (delayed after power on)

Those actions and their use are described in detail in Section 5.6.1, “Maintenance”.

1.2.4. USB connector + RSS voltage contacts ( S )

Slot „S“ is shortcut of “Service”. It contains system connectors – standard USB port and a pair of contacts for RSS voltage output (red + green ones).

USB port

USB-A port is designed for access to RAy management through USB/WiFi adapter or USB/Eth adapter plugged in to. More information about installation and configuration of available adapters can be found in Quick Guide and in Section 5.4.3, “Service access” (part “USB Accessories”).


Only RACOM recommended adapters are supported. See section Access adapters.

RSS voltage output

RSS (Received Signal Strength) is a basic parameter used for directing antennas to the optimal direction. RSS output voltage is calibrated to be proportional to actual RSS dBm (for example 0.547 V means RSS –54.7 dBm). Thus a standard digital voltmeter allows to see RSS value in a digital form interactively during the antenna alignment. More information about RSS voltage output usage is in Section 4.7.2, “Directing antennas” (part “Voltmeter”) together with several alternative ways to get this value by other methods.

1.3. Status LEDs

Status LEDs ( AIR - SYS - ETH )

Fig. 1.5: Status LEDs ( AIR – SYS – ETH )

Tab. 1.1: Meaning of LED status indicators

ETH1, (10/100/1000)
Flashing irregularlyLink Activity
Permanently litPort without operation (Auto Negotiat. was carried out)
Flashing regularlyAuto Negotiation in progress
Flashing irregularlyLink Activity
Permanently litPort without operation (Auto Negotiat. was carried out)
Flashing regularlyAuto Negotiation in progress
Permanently litUnit is starting
GreenPermanently litSystem OK
Flashing regularlyHW button pushed on the unit running
Factory defaults in progress
Firmware writing in progress. DO NOT POWER OFF !!
RedPermanently litSerious system error
Flashing regularlyHW button pressed during unit start
(HW button continuously pressed)
Flashing intermittentlyUnit in the service Linux
AIRGreenPermanently litLink: OK
Flashing intermittentlyLink: Connecting
RedPermanently litLink: Single
  • Flashing regularly            500 ms on / 500 ms off

  • Flashing intermittently     50 ms on / 950 ms off

  • Flashing irregularly          by passing frames


1.4. Technical parameters

Basic technical parameters are stated in Chapter 9, Technical parameters .

RAy links are transparent for IP and UDP Ethernet traffic (all protocols passes through including MPLS and many others) except following packets:

  • Management packets targeted for RAy units itself

  • Special packets for protocols explicitly mentioned in this manual which are somehow processed by RAy units (like PTP)

  • Packets which did not went through and were discarded due to capacity limitation of the link (and QoS settings).

1.5. Dimensions

Communication unit ODU

Outer size
  • 244 x 244 x 157 mm

  • RAy2-10 — 2.8 kg

  • RAy2-11 — 2.8 kg

  • RAy2-17 — 2.5 kg

  • RAy2-18 — 2.7 kg

  • RAy2-24 — 2.5 kg

Diameters of supplied antennas

RAy2 units are ready for direct mounting to:

Individual datasheets are accessible here.

Tab. 1.2: Overview of LEAX-RAy antennas

 10, 11 GHz 17, 18 GHz 24 GHz
30 cm30.1 dBi30 cm34.7 dBi30 cm37.0 dBi
60 cm35.2 dBi60 cm39.7 dBi60 cm42.4 dBi
90 cm38.5 dBi90 cm43.5 dBi90 cm45.7 dBi
120 cm41.5 dBi120 cm45.5 dBi120 cm48.4 dBi

Tab. 1.3: Overview of Jirous antennas

 10, 11 GHz 17, 18 GHz 24 GHz
38 cm29.0 dBi40 cm34.8 dBi40 cm36.8 dBi
65 cm35.5 dBi68 cm38.6 dBi68 cm41.7 dBi
90 cm37.5 dBi90 cm41.0 dBi90 cm44.0 dBi
120 cm41.0 dBi120 cm43.7 dBi120 cm46.6 dBi

Andrew (Class 2 or 3 or 4) or traditional Arkivator antennas can also be used but require an antenna mounting kit. Flexible waveguide is a general-purpose option for any antenna usage.

Name plate

The plate contains name, bar code record, CE label, etc.:

  • Type – RAy2 product line identification

  • Code – detailed identification of the unit type (for details see Section 1.6, “Ordering codes” ).

  • S/N – serial number, MW link consists of two separated units with two different serial numbers

  • QR code – www link to the latest version of the User manual

  • Power DC supply connector polarity marks


Name plate

Fig. 1.6: Name plate

1.6. Ordering codes

The proper pair (from the same row) of Lower and Upper units should be selected when ordering the microwave link. This is not valid for RAy2-17 and RAy2-24 units. In such a case the same unit is used for both sides of the link.

Tab. 1.4: Ordering codes

SW key possibilities, valid for RAy2-10, 11, 17, 18, 24:

  • RAy2-SW-200             SW feature key – Capacity up to 200 Mbps

  • RAy2-SW-360             SW feature key – Capacity up to 360 Mbps

  • RAy2-SW-200-360      SW feature key – Capacity upgrade from 200 to 360 Mbps


The RAy2-10, RAy2-11 and RAy2-18 units must be mounted with the same polarization while the units RAy2-17 and RAy2-24 must be mounted with reverse polarity, see Cross polarization.