Cel-Fi G51 Cellular Coverage Repeater (Celfi) – Telstra, Optus 3G 4G LTE 5G

Cel-fi offers a range of 3G/4G/LTE cellular signal amplifiers that are approved for use on Australian networks. Some models such as the G51 support 5G (3500 GHz) boosting.

Select Cel-fi GO & Solo models are legal and approved for use on Australian networks. Find more information from the ACMA here.

Cel-fi Mobile versions are suitable for vehicles, trucks, boats, caravans that are on the move etc. This version allows for the Cel-fi unit to move or switch between towers during transit. Cel-fi Mobile versions: G31 (some models), G32

Cel-fi Stationary versions are suitable for buildings, homes or situations where the Cel-fi repeater and donor antenna will not move. Stationary mode allows for the unit to function with higher gain.

Stationary versions: G31 (some models), G32, G41, Pro, Solo, G51

The Cel-fi G31 is a single band (1 channel) repeater, whereas, G41 & G51 models support dual-band (2 channels).

The Cel-fi G31 is suited to areas where limited cellular bands are available or more specifically, 3G and rural areas. The G31 supports the following bands:

Telstra: 700, 850, 1800
Optus: 700, 900, 1800

The Cel-fi G41 & G51 are more powerful repeaters that are capable of repeating 2 bands at any given time with a wider support of cellular band compatibility. The G41 offers support for 5G NR operation in traditional LTE bands.

The G41 supports the following bands:

Standard Version: 700 (Lower), 850,  900, 1800, 2100, 2300, 2600 (note: 700 channel not supported for Vodafone)

Vodafone Spec Version*:  700 (Upper), 850, 1800, 2100, 2300, 2600

The G51 supports the following bands:

Standard Version: 700 (Lower), 850,  900, 1800, 2100, 2600 (note: 700 channel not supported for Vodafone), 3500 (N78-5G)

Stationary versions: G31 (some models), G32, G41, Pro, Solo, G51

Cel-fi G31 series are available in mobile and stationary versions. The G31 mobile version will be the most common Cel-fi for a vehicle, truck, caravan.

Cel-fi G32 series may be switched between Optus or Vodafone for support of a singular network once registered. You may change the network registration of the repeater at any time should your requirements change.

Cel-fi G41 series may be switched between Telstra or Optus or Vodafone for support of a singular network once registered. You may change the network registration of the repeater at any time should your requirements change.

Cel-fi G51 series may be switched between Telstra or Optus or Vodafone for support of a singular network once registered. The G51 also support NR87-5G (3500GHz). You may change the network registration of the repeater at any time should your requirements change.

No Cel-fi product will support the simultaneous “repeating” of more than one network.

Cel-fi G31 series are locked into specific networks off the shelf.

Cel-fi G32 series may be switched between Optus or Vodafone for support of a singular network once registered. You may change the network registration of the repeater at any time should your requirements change.

Cel-fi G41 & G51 series may be switched between Telstra or Optus or Vodafone for support of a singular network once registered. You may change the network registration of the repeater at any time should your requirements change.

This is possible, however, it cannot be facilitated with one Cel-fi repeater.

A Cel-fi repeater and dedicated donor antenna will be required for each network that you wish to support. In some cases, a single donor may be utilised when all suitable carrier signals are located on the same cellular tower. With the addition of the right combining hardware and service antennas – we can design a kit and solution to meet your requirements.

All Cel-fi units are registered and configured via the Cel-fi WAVE app for Android and Apple (iOS).

Stationary/Building/Home:
Whilst we highly recommend a professional installation and configuration, many users choose to self-install. The Cel-fi app will display real-time signal settings that can be used to fine tune your installation (for example, the direction/aspect of a donor antenna for a stationary/building can be fine-tuned by interpreting signal values in the app as the direction of the antenna is rotated etc.)

Mobile/Vehicle (on the GO):
We recommend setting your Cel-fi to “Automatic” via the WAVE app. This will let the Cel-fi handle all settings and function automatically.

Alternatively, you may set your Cel-fi to “3G” or “4G” or even specific bands. For example, rural areas may benefit from locking the Cel-fi to 3G only.

Most Cel-fi kits readily available online will feature one or two service antennas. As a rough guide, one service antenna will provide signal to one room (approx 200 square metres). Performance is also entirely dependent on the quality and power of the source (donor) signal that the Cel-fi is repeating.

Larger projects with greater coverage areas and antennas will require design, hardware and balancing considerations. Contact us to talk you through the options available for low-power, off-air repeaters and DAS solutions.

We recommend Cel-fi G51 or G41 for all stationary, home and building solutions as they are multi-band repeaters – providing for increased coverage and channel support over G31 stationary versions. If you only need to repeat one good quality signal such as 700 or 1800 (4G) then you can consider the G31 stationary series.

Sure, we can help you! However, an off-the-shelf kit will not suffice for your requirement. We will be able to design and recommend the appropriate hardware and DAS (distributed antenna system) for your needs including installation and commissioning.

Multiple individual instances of Cel-fi systems will not solve your coverage issues – leading to hand over issues, interference and noise. In some case, the units will not function at all.

As a guide, you should be noting the following variables…

Power (RSRP)

Measured in negative (-) dBm where the closer to zero the value, the stronger the signal. The range is typically -60 (Stronger) to -130 (Very weak to unusable).

Quality (RSRQ)

Measured in negative (-) dB where the closer to zero the value, the stronger the signal. The range is typically -5 (Stronger) to -20 (Very weak to unusable).

Noise (SINR)

Measured in negative dB where a positive number is a better quality signal. The range can vary from -20 to +20 whereby positive values are always better.

Omni or Omni-Directional antennas receive signals equally from all directions, providing consistent coverage over a broad area where cellular signals are considered good. The disadvantage is they cover a smaller range and may not be able to pick-up signals from far cellular towers.

Directional antennas are recommended over omni, particularly for stationary installations. They are generally more powerful with a higher gain, meaning a narrower beamwidth. Further distance and less noise are key factors as to why directional antennas (or yagi) are preferable for Cel-fi stationary.