Cambium 650 Core Solution

The words “Cambium”, “Motorola”, and “Orthogon” among radio communication operators are widely known and are associated primarily with positive feelings. Almost in every city in the country, you can see characteristic elongated devices in offices, gas stations, houses, and sometimes pmp100 subscriber devices, better known as anopy, known for their stable performance even in difficult interference conditions, in a flattened reflector. Less often, you can see the manufacturer’s PTP series, as these productive solutions are usually found on masts, and channels with a range of up to 100 kilometers are built on them.
The key advantage of the systems of these model series is high performance, the ability to work with obstacles in the Fresnel zone, the reliability of the solution, and the disadvantage mentioned at the beginning is the high cost.
However, in the coming year, cambium overcomes the stereotype and offers a more affordable mainline solution - with all the positive qualities of the 600 series, higher productivity and lower heat generation.
So today we’ll explore the Cambium 650 Series , which offers us 450 Mbps of bandwidth, delays of less than 2 ms and high range.

Further, under the cut - a lot of graphs, tables and screenshots.

The 650 series equipment is a continuation of the idea of ​​the 600 line - a high-performance highway capable of operating even if there are obstacles in the Fresnel zone. In developing the system, the tasks were to preserve the positive features of the solution, increase productivity and eliminate the following disadvantages:

• High cost;
• Large block;
• High power consumption.

Comparing the solutions, it is safe to say that the tasks have been solved - the weight and energy consumption has decreased, the performance has increased:

	650 series	600 series
Performance, MB / s	450	300
Temperature conditions, ° range	-40 ... + 60	-40 ... + 60
Power consumption, W	thirty	55
Mass of active part, kg	4.1	4.3
Cable ports	Gigabit Ethernet, SFP, 802.3at power supply	Gigabit ethernet

Functionally, the device is an all-weather solution with a gigabit port and an SFP slot, thanks to which the system can be installed on the removal of more than 100 meters from the thermal container.
Power is supplied via twisted pair; There are models with both built-in antenna and a connector for connecting external antennas.
From a network point of view, the system functions as a bridge, with the ability to:

• Vlan filtering;
• Prioritization of traffic;
• Router Awareness of Span Overload.

Management is carried out through the graphic menu, however there is both telnet and support for control systems.
The performance of the system is regulated by the license - thus, the primary costs of the system are reduced, and with increasing requirements, it is enough to purchase a file to extend the performance to 125, 250 or 450 Mbps.
I would like to mention the possibility of temporarily activating a license of the maximum type, which allows you to assess whether your customers have a need for such performance. The system works on a temporary license for up to 2 months, while the license can be suspended and renewed - this is very convenient for test equipment sets.
Let's see what the new line can offer in comparison with the solutions of other manufacturers that are common on our market:
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	Cambium 650	Infinet omx	Ubiquity rocket
Productivity is useful, Mb / s	450	210	200
Package performance, kilopacket / s	900	200	20
Power and sensitivity for 200 Mbps, dBm	25; -69	23; -75	21; -75
Power and sensitivity in maximum performance mode, dBm	23; -62	23; -75	21; -75
Description	The development of the famous mainline series 600	Well-known broadband access solutions in Russia. The model range includes both a point-to-multipoint family and solutions for highways. The advantages of the equipment: high performance, a variety of traffic processing settings, cold resistance.	Well-known low-cost solution, the advantage is the high power at a low price.

According to the analysis results, one can note a significant advantage of the Cambium solution in the main parameters:

• Performance;
• Processor power;
• Output power for complex modulations;
• Spectrum analyzer, working without turning off the radio channel;
• The ability to receive and transmit at different frequencies;
• SynchroEthernet support;
• The time division of the signal, the ratio of traffic (incoming to outgoing) in the proportions 1: 1, 1: 2, 2: 1, is adaptive.

Test results

We tested the 650 Series device using Optiview XG hardware generator and power meters.
Maximum performance in the main frequency bands was checked by increasing data flow (green fill — applied load, marks — achieved capacity). Traffic is transmitted through the channel, reflected and received by the transmitter. Thus, the results are viewed as a full-duplex, bidirectional data stream.







Please note: in this test we used large frames - while, according to statistics from most of our clients, the frame size of modern networks is now in the vicinity of 300 bytes.
We will re-test the performance using frames of the following sizes: for Cambium, Infinet we use 64 bytes, for Rocket - 128 bytes.





Thus, in performance Cambium wins a clear victory.

Performance test results for intermediate frame sizes, tabulated:

Performance in various frequency bands

Clear and beautiful graphics of bandwidth in the frequency bands common to all solutions (abscissa axis - frame size in bytes, ordinate axis - bandwidth in Mbps):

20 MHz:


40 MHz:


For those who want to repeat the test, I draw your attention to the fact that traffic compression is enabled in Infinet - therefore, a random packet filling generator is required. If measured with uniform content frames, the performance of packets of a certain size exceeds 170 Mbps.

Receiver sensitivity check

Probably, many have noticed that the sensitivity of the considered line with the maximum performance is lower than the compared models. On the one hand, this is logical: the useful performance of 10 Mbit / s per MHz forces the use of modulation with 256 positions, while competitors use 64 positional modulation, but there is a difference in measurement methods.
We will check with attenuators at what level of reception the system supports productive modulations, while loading the channel with traffic.

Testbed layout
Cambium, 40 MHz spectral width

	Declared sensitivity, dBm	Measured sensitivity, dBm
256QAM	-62	-56
64QAM	-64	-63
16QAM	-69	-67

Ubiquiti, 40 MHz spectral width

	Declared sensitivity, dBm	Measured sensitivity, dBm
64QAM	-75	-61
16QAM	-84	-75

We see that the Ubiquiti system does not set the maximum speed at the specified signal level, unlike Cambium - the use of chipsets for mobile wimax allowed to work effectively with a significantly smaller fade margin, use modulation with 256 positions and significantly improve the possibility of combining networks due to a more strict spectrum mask.
We see that on modulations up to and including 64QAM, the system showed a sensitivity corresponding to the stated one, and at maximum modulation, the sensitivity is somewhat less.
Ubiquiti equipment showed a significant difference in the declared and tested sensitivity.

Graphs of real and declared sensitivity, adopting a attenuation of 1.5 dB in the cable (ordinate - dBm):


Thus, the solutions on the Wi-fi platform, we did not see any advantages other than price. If we add that Cambium has full-fledged MIBs, the line will soon be added to the CNS control system, and the company's radio planning product will calculate the channels with obstacles for free, then the winner of the comparison becomes obvious. Well, we are waiting for practical confirmation outside the laboratory - in the spring we are going to make a comparison of products on real radio channels.

We also plan to write an article about the new 650S solution. This is a modification of the 650 series, specially designed for the routes between cellular stations of the 3rd and 4th generations.

A bonus to detailed testing of the technical side of the device, without claiming to be authorized courses, is to take a quick look at the main menu of the device.