Premlink - Your Trust RFoG ONU / MDU Manufacturer
What is RFoG (Radio Frequency over Glass)?
RFoG, or Radio Frequency over Glass, is a technology that replaces the coaxial component of a hybrid Fiber-Coaxial (HFC) network with a Passive Optical Network (PON) architecture. This new method improves efficiency and performance when delivering cable services via fiber optics. The Society of Cable Telecommunications Engineers (SCTE) has taken steps to standardize this technology by releasing detailed specifications for RF over glass fiber in the document ANSI/SCTE 174 2010, which outlines the technical requirements and best practices for implementing RF over Glass systems in modern telecommunications networks.
Premlink RFoG Product Series Overview
Premlink’s popluar product, PL10x seres, is totally comply with SCTE 174 2010 standard, we product thise series in a large quantity for long years. It is super reliable with excellent performance, PL10-3A is a classic product with optical in/out into one connector. PL10-4A has GPON pass through port and PL10-6A has XGSPON + GPON pass through port
RFoG ONU & MDU Configuration Selection Guide
Input / Output | Output Level | Laser Type & Power | Return Laser (Typical) | Band Split | Power Adapter |
|---|---|---|---|---|---|
Forward Only | 78dBμV | DFB 1mW | 1490nm | 30 / 47MHz | Chinese Standard |
Forward and Return | 80dBμV | DFB 2mW | 1510nm | 42 / 54MHz | Euro Standard |
GPON Pass | 86dBμV | DFB 3mW | 1530nm | 65 / 85MHz | US Standard |
XGSPON+GPON Pass | 95dBμV | Isolated DFB 1mW | 1570nm | 85 / 105MHz | UK Standard |
/ | 105dBμV | Isolated DFB 2mW | 1590nm | 108 / 258 MHz | Japan Standard |
/ | / | Isolated DFB 3mW | 1610nm | / | ... |
Use this configuration guide to match the RFoG ONU to your specific network requirements:
- Input/Output: Choose ‘Forward Only’ for simple broadcast TV, or ‘Forward and Return’ for interactive services.
- Output Level: Match the dBμV to the distance to the subscriber’s home or in-building distribution needs..
- Laser Type & Power: no lsolated or Isolated DFB lasers for return path quality signal.
- Return Laser Wavelength: Must match the head-end’s return path optical receiver.
- Band Split: Select based on your upstream/downstream frequency plan.
Key Benefits of RF over Glass Technology
Cost-Effective Network Evolution
RF over Glass technology provides cable operators with a cost-effective network expansion and upgrading solution, allowing cable operators to continue to use existing HFC transmission equipment and subscriber terminal equipment to deploy new FTTP networks, greatly reducing the capital investment in network transformation.
Preserve Existing Infrastructure & Billing Systems
With this technology, cable operators can transmit a variety of cable services over optical fiber and can continue to use the original equipment and billing systems, CMTS platforms, front-end equipment, set-top boxes, conditional access and cable modems.
Simplified FTTP Migration
Cable operators in the transformation of the original HFC network, only in each subscriber’s residence to install a new miniature optical station known as an optical network unit (ONU), used to convert optical signals into electrical signals, this process replaces the traditional by the deployment of the HFC network in the high-level optical station to perform the function of the radio frequency network equipment remains unchanged, but only the optical network terminals from the optical station to the subscriber’s residence.
The best thing about RFoG for a cable provider is that it lets them do a “node-splitting” or “deep-fiber” upgrade without having to touch the headend or customer premises equipment (CPE). Operators can instantly increase bandwidth capacity, lower noise in the return path, and extend network reach by simply replacing the coaxial distribution leg with an RFoG ONU at the home and a matching reverse receiver at the headend.
This “outside plant only” upgrade keeps all of their money in DOCSIS platforms, set-top boxes, and billing integration, and it makes the switch to FTTP as easy as possible with as little disruption to operations as possible.
How Does RF Over Glass (RFoG) Work?
Forward Path Operation
In the Cable TV bidirectional transmission network constructed by applying RF over Glass technology, the forward channel is exactly the same as the traditional HFC network, adopting broadcast transmission service, and the fundamental difference is in the return channel.
Return Path & Burst Mode Operation
In the Cable TV bidirectional transmission network constructed by applying RF over Glass technology, the forward channel is exactly the same as the traditional HFC network, adopting broadcast transmission service, and the fundamental difference is in the return channel.
Using RFoG technology optical node, the reverse optical transmission component of the laser works in a ‘burst’ mode and CMTS the same time division control technology (TDM) to control the optical node back to the laser ‘on’ or ‘off’ working state, so as to achieve the following results The same time-division control (TDM) technique as CMTS is used to control the ‘on’ or ‘off’ operating state of the optical node’s return laser, so that only one optical node is allowed to communicate with the CMTS head-end at any given point in time.
When the modem at the user’s end does not send a return RF signal, the optical node’s reverse laser is in the off state; the optical node’s reverse laser is turned on only when the modem sends a return RF signal, and when the modem’s return RF signal has been sent, the reverse laser is immediately turned off.
Signal Aggregation and Noise Suppression
The return optical signals from multiple optical nodes can be aggregated through an optical splitter, and then transmitted back to the split front end using a single optical fibre, and then received by an RFoG dedicated reverse optical receiver and sent to the CMTS uplink receive port.
After the introduction of RF over glass technology into the traditional HFC transmission network, not only can it easily achieve the forward shift of optical nodes, but also can effectively suppress the burst noise of the uplink backhaul channel.
Frequently Asked Questions (FAQ) about RFoG ONU/MDU
RFoG is a technology standard (ANSI/SCTE 174) that lets cable companies use a Passive Optical Network (PON) architecture to send their regular RF video and DOCSIS data services. It replaces the coaxial cable part of an HFC network with fiber, but the headend equipment (CMTS, video servers) and customer equipment (cable modems, set-top boxes) stay the same.
A standard GPON ONU is made to end a native GPON signal and usually has Ethernet outputs. An RFoG ONU is made to pick up a 1550nm RF video signal and change it into RF for TVs. A lot of Premlink RFoG ONUs, like the PL10-4A/6A, are hybrid devices. They convert RFoG video and send GPON/XGSPON data wavelengths to a separate data ONU, which lets you get triple-play services over one fiber.
SCTE 174 is the industry standard that makes sure that RFoG products from different companies work together properly. Compliance makes sure that Premlink's ONUs will work perfectly with standard headend equipment and CMTS burst-mode control. This stops problems like laser clipping or wrong return path timing. Our PL10x series is fully compliant, so you can be sure it will work.
A lot of homes share the return path in an HFC network. RFoG does something similar with Time Division Multiple Access (TDMA). The CMTS decides which modem can send data. When a certain modem sends a signal, its RFoG ONU picks up on the burst of RF energy and quickly turns on its return laser. The laser turns off right after the burst ends. This "burst mode" operation stops optical beat interference and lets a lot of ONUs share one fiber back to the headend.
We usually send out sample orders within 10 to 15 business days because we are a dedicated factory with high-volume production lines for our PL10x series. The time it takes to fill a bulk order depends on how many items you order.