Poynting, a company specialising is antenna design and manufacturing in South Africa, has issued a public service announcement warning that it is seeing a large number of sub-standard antennas being sold to the public. According to the company, people are being enticed by the appealingly similar or better specifications when compared to the reputable brands, but at much lower prices.
Dr. Fourie, who is a product specialist and chairman at Poynting Group, reports that they have tested some of these substandard antennas and can confirm that their performance is nowhere close to what their specifications imply: “These specifications are not only misleading, but the antennas are terrible,” he stresses. He goes on to say that tests performed by Poynting showed that antenna specifications of these antennas are highly overstated and often have horrendous radiation patterns with severe voltage standing wave ratio (VSWR) issues and antenna gain figures being exaggerated.
The antenna is an intricate part of the whole solution, and this seemingly simple device can easily negate the performance of the equipment it is connected to. “We often see expensive router and gateway equipment being installed, only to find out that the whole system’s performance was compromised by using poor performing antennas to save a few Euros,” continues Fourie, “You purchase an antenna and wonder why your system is not performing as expected. It is difficult for the end customer to determine if it is due to the antenna, or if the problem is with the connected equipment e.g. LTE/Wi-Fi router, M2M gateway, etc.”
To illustrate the extent of the problem, Fourie points to the case of one antenna which is being sold internationally as being an 88 dBi desktop antenna. He says this is a ludicrously high gain being claimed, and in reality it is a low gain antenna with very poor characteristics for its type. “The quoted 88 dBi is physically impossible even for an antenna hundreds of times larger in size. This is how far some suppliers will go to market their antennas, and they are quite successfully selling these antennas to unsuspecting consumers. A consumer could have purchased an antenna with much lower gain specifications from a reputable supplier and the customer experience would be much better,” he says.
As a further example, Fourie mentions another dubious antenna which was tested, which was designed and marketed for installation on a vehicle. “The antenna actually appeared to have reasonable test results – at first glance – but as soon as it was installed on a vehicle, the antenna’s performance went completely haywire. The VSWR was as high as 16:1, which is terrible.” He says the problem was that the antenna manufacturer never considered the effect of the ground plane on the antenna, which affects the performance of such an antenna when being mounted on a metallic surface – ironic considering the application it is intended for. Fourie says someone installing such an antenna might not notice it immediately, but will continuously have a problem with their communications reliability.
Poynting also looked at an antenna, suspiciously similar to one of its own antennas, only to discover it had several dry solder joints, the result of poor manufacturing quality and quality control. “Needless to say, this antenna was not even tested as it would have been a waste of time,” says Fourie.
Another example where an alleged copyright infringement was investigated, was where a company based in Asia produced an antenna which was an almost exact copy of a Poynting registered design for an older version of its antenna. Even though the antenna was almost a one to one copy, it performed poorly when compared. The company producing this antenna marketed the antenna at a much higher gain than the one it copied. “Customers are purchasing this type of antenna with poorer performance for almost the same price as the real thing, just to save a few bucks,” Fourie warns.
In closing, Fourie advises that consumers rather purchase from reputable companies. “The antenna might be a small portion of the cost of a communications system, but it can have devastating effects which can compromise the value of the entire system,” he concludes.