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Interference Problems

Slow service and intermittent loss of service is most commonly caused by radio frequency (RF) interference. Devices transmitting and receiving at or near the same frequencies can experience degraded performance, and even failure. Effects can range from unnoticeable to severe. A description of our system will help customers locate common potential sources of interference.
Our current network structure is based on 802.11(b) to the customer from our towers. The frequency spectrum utilized by 802.11 is license-free, meaning that active transmission in the spectrum is allowed without any of the normal filing and application procedures through the Federal Communications Commission (FCC). What this means is that anyone can deploy and use the equipment when and wherever they want. There is no recourse for other operators stepping on your frequencies (transmitting on the same frequencies).
The FCC has a few specific requirements for the spectrum, most of which are dealt with by the manufacturer of the equipment. Manufacturers are required to submit their systems for review and approval through the FCC. Sometimes, though, manufacturers will stretch specs during production. Additionally, components that were never submitted as a complete system, can be assembled in such a way that violates FCC requirements. This is not legal, but difficult for the FCC to enforce due to the number of devices and systems in operation. Violations occur primarily as a result of complaints filed by individuals and investigated by the FCC.
Multiple operators of 'Wi-Fi' or 802.11 equipment in a single geographic area present a very serious issue. There isn't enough spectrum to go around, and since the spectrum is unlicensed, there is no legal recourse for entrenched operators whose systems suddenly become plagued by interference from a new operator setting up shop. Working closely with competitors becomes mandatory for the successful deployment and continued operation of the multiple systems.
As with many consumer electronics equipment, 802.11 equipment falls under Part 15 of FCC Rules. These rules simply say that 'Operation is Subject to the following conditions: (1) this device may not cause harmful interference (outside of the intended spectrum), and (2) this device must accept any interference that may cause undesired operation. This is commonly found on many consumer electronics products.
There is a proliferation of such devices that operate between the frequencies of 2.402GHz and 2.472GHz: cordless phones, wireless video cameras, wireless network gear, PDA's, garage door openers, baby monitors, and the list goes onů
Any such device has the potential to interfere with the equipment that we place at the customer's premise to use our high speed Internet services. For the most part, these devices will not prove to be a persistent source of interference, which can be tolerated by the 802.11 specification (using Direct Spread Spectrum Sequencing technology). However some 2.4GHz phones and 2.4GHz video devices from some manufacturers seem to cause more headaches. To complicate the matter, a neighbor, if close enough, can have devices that interfere with our equipment. We will maintain a list of specific devices at the end of this page that are known to cause interference.
Also, if the customer has a wireless access point or router, they must ensure that they are not operating that device on a channel (frequency) that interferes with our equipment. A list of tower channels is available here.
Lastly, microwave ovens with worn or missing RF seals, licensed (and unlicensed) ham radio operation and radar installations are other potential sources of interference. Finding the source can be a hair-pulling experience, due to the often intermittent nature of the interference and lack of instrumentation to detect source direction and frequency. Spectrum analyzers can be employed to find such sources of interference, but they are expensive.
INTERFERING EQUIPMENT LISTING


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