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Wireless Growth & Wireless Interference
windowpain writes "An article in Monday's Washington Post says "The explosive growth of the mobile phone industry has crowded and tangled the nation's airwaves to such an extent that wireless company signals are increasingly interfering with emergency radio frequencies used by police and firefighters, public safety agencies said." Wifi is not a problem, evidently. Understandable, given its short range."
"Wifi is not a problem, evidently. Understandable, given its short range." Yah, that and the fact that the public safety networks operate in the 700 and 800 Mhz bands, whereas 802.11a and b currently operate primarily at 2.4 Ghz.
- If spectrum is reshuffled, could this be an opportunity for the wifi-friendly (but still evil) Powell to allocate more unlicensed spectrum?
- Alternately, does the emergence of the interference bogeyman in such a prominent publication imply a tough PR road for more free spectrum?
- Could this be an opportunity for the cell carriers operating in the 800MHz band to switch to different technologies, or roll out newer services?
- Could these sorts of problems be used to get some federal money thrown toward development of software radio? would multi-format devices help avoid this problem?
As the submitter mentions, these emergency bands don't appear to be abutting or affecting the 2.4GHz range, but I imagine these issues will be relevant as wifi expands and interference problems begin cropping up.Bureacracy will inevitably develop when such systems reach a certain size, and bureacracies will inevitably suffer inefficiencies. But I don't think adding profit motive to the equation necessarily makes the systems run any better -- it just shifts the mandate of the organization to revenue generation by system maintenance, rather than purely system maintenance -- and consequently opens the door to Worldcom/Enron-type problems.
I would rather not have market forces detemining whether I get 911 service on my cell, thanks
To preface my comments, I am a holder of a First Class Radiotelephone FCC license, and an active Amateur Radio Operator. I have been involved in communications of all types, from TV and FM transmitters to engineering two-way radio installations. Now with that said --
What a load of crap! It's not the problem of the wireless providers, it's a problem of coverage due to poor system engineering.
Most, if not all, 800 mhz emergency service systems operate on what is call a "Trunking System". What this is, essentially, a system of linked towers that communicate with the vehicle or officer on the street, then relay from tower to tower ultimately connecting to either the dispatcher or another officer. These systems are designed to be interoperable with each service, such as police, fire, ambulance, etc, so a single dispatch facility can communicate with everyone, and all services can communicate with each other.
To work effectively, you must have sufficient towers properly placed to assure that there is no dead zones. Given the expense involved in site purchase, permits, tower erection, equipment installation, and backup generators, the bare minimum is pretty much the rule. Plus, you cannot physically survey the entire area of coverage, you use topo charts to try to make sure your engineering is sound.
To blame the wireless providers is silly and stupid. Modern 800 mhz equipment is very selective, most newer systems operate via spread spectrum digital, and the chances of interference are minimum.
Additionally, emergency services have priority so if there is a provable case of direct intererence, the wireless provider must take steps to either stop the interfering signal, or cease operations entirely.