الكل
← Back to Squawk list
FAA: Airlines must retrofit faulty altimeters “as soon as possible”
The Federal Aviation Administration says it finally has a plan for the industry to replace or retrofit airplane altimeters that can't filter out transmissions from outside their allotted frequencies. The altimeter problem has prevented AT&T and Verizon from fully deploying 5G on the C-Band spectrum licenses the wireless carriers purchased for a combined $69 billion. The FAA was urging airlines to retrofit or replace altimeters in recent months and now says it has finalized a plan. An… (arstechnica.com) المزيد...
Sort type: [Top] [Newest]
If there is no manufacturers building approved filters, how are the airlines supposed to install said filters? Does anyone know if this is correct?
A few years ago the GPS industry had the same problem. One man then designed a proper filter for his GPS receivers while the rest of the industry continued to whine about the transmitter being too close to their state of the art designs. He then went and gave out his filter's design info for free.
They’re being built overseas.
So what else is new!
Ain't that the Truth... We have been retrofitting planes for Decades! Look at GA with the Avionics Upgrades that Rival many Airliners.
As a licensed amateur radio operator and radio/electronics enthusiast for 40+ years (and from reading much information about this issue), it sounds to me like it IS, in fact, the aircraft equipment that is lacking, not the cell-phone carriers.
This all seems to be clear case of the aircraft using older (?), or perhaps technologically obsolete (or at least deficient) equipment designs. If the altimeter receivers have such poor band/frequency selectivity and lack of out-of-band dynamic range, that they are (or will be) interfered with by a signal from outside of their specific operating frequencies, then they are the problem. If the "offending" transmitter(s) (in this case, the 5G cell-phone signals) are within their operating parameters, then it is not the responsibility of the transmitter to be corrected, but rather the [poor] receiver to be corrected.
As a radio operator, if I'm transmitting on a legally-assigned frequency, and my transmission characteristics are within the "legal" and acceptable operating parameters (for modulation bandwidth, carrier power, etc.), and yet my transmissions are somehow interfering with your equipment (which may have poor selectivity and lack of dynamic range), I am not at fault, YOUR equipment is. Therefore, it is not my responsibility to correct your faulty equipment.
While it seems like the FCC (and FAA) should have perhaps been more "in-the-loop" early-on, and explored the possibilities of any cross-band interoperability issues beforehand, the FCC cannot control the technical issues of the poor receiving equipment; receivers don't create interference, they only "hear" it. The FCC can only allocate band assignment and usage, and regulate the TRANSMITTERS used on those bands. In addition, the FAA probably created (or had a hand in creating) the spec's for the altimeter receivers, so they should have also known there might be a conflict.
Imagine if the situation were reversed, and the 5G cell-phone carriers were experiencing some interference from the aviation altimeter transmitters. Would the altimeter transmitter manufacturers be required to pay for "fixing" (i.e., "improving") the 5G cell receivers? Of course not! That said, however, if the altimeter transmitters were operating in such a way (out-of-band spurious signals, etc.) as to be CAUSING the 5G interference, then it would be on them to correct their equipment.
Lastly, since the new 5G cell equipment is most likely the latest, greatest, state-of-the-art radio gear, it is VERY unlikely that their transmitters would be operating, in any way, outside of their very tight and regulated specifications.
This all seems to be clear case of the aircraft using older (?), or perhaps technologically obsolete (or at least deficient) equipment designs. If the altimeter receivers have such poor band/frequency selectivity and lack of out-of-band dynamic range, that they are (or will be) interfered with by a signal from outside of their specific operating frequencies, then they are the problem. If the "offending" transmitter(s) (in this case, the 5G cell-phone signals) are within their operating parameters, then it is not the responsibility of the transmitter to be corrected, but rather the [poor] receiver to be corrected.
As a radio operator, if I'm transmitting on a legally-assigned frequency, and my transmission characteristics are within the "legal" and acceptable operating parameters (for modulation bandwidth, carrier power, etc.), and yet my transmissions are somehow interfering with your equipment (which may have poor selectivity and lack of dynamic range), I am not at fault, YOUR equipment is. Therefore, it is not my responsibility to correct your faulty equipment.
While it seems like the FCC (and FAA) should have perhaps been more "in-the-loop" early-on, and explored the possibilities of any cross-band interoperability issues beforehand, the FCC cannot control the technical issues of the poor receiving equipment; receivers don't create interference, they only "hear" it. The FCC can only allocate band assignment and usage, and regulate the TRANSMITTERS used on those bands. In addition, the FAA probably created (or had a hand in creating) the spec's for the altimeter receivers, so they should have also known there might be a conflict.
Imagine if the situation were reversed, and the 5G cell-phone carriers were experiencing some interference from the aviation altimeter transmitters. Would the altimeter transmitter manufacturers be required to pay for "fixing" (i.e., "improving") the 5G cell receivers? Of course not! That said, however, if the altimeter transmitters were operating in such a way (out-of-band spurious signals, etc.) as to be CAUSING the 5G interference, then it would be on them to correct their equipment.
Lastly, since the new 5G cell equipment is most likely the latest, greatest, state-of-the-art radio gear, it is VERY unlikely that their transmitters would be operating, in any way, outside of their very tight and regulated specifications.
