The U.S. military worries about interference between the 5G network and the GPS system |
Ministry of Defense officials criticized a previous FCC decision authorizing the US Satellite Communications Company (Ligado) to create a nationwide broadband cellular network that could interfere with GPS signals important to military operations.
Military officials told the US Senate Military Committee that the GPS system is at great risk of interference from the 5G networks approved by the FCC, saying that the FCC decision will endanger GPS users. There is a risk.
This happened after the FCC approved the new 5G network, although the Ministry of Defense claimed that it would interfere with GPS services, while the Ministry of Defense media propaganda Dana Desy contradicted the FCC claim that the imposed Ligado network would protect GPS from interference .
Ligado plans to use a range of satellite and terrestrial communications for its network, rather than compete directly with Verizon, AT&T and T-Mobile, but plans to provide a dedicated network for industrial companies, IoT services, experimental and wireless systems for other commercial use cases. Economy and government.
When the Ligado (FCC) plan was approved last month, the agency requested a 23 MHz protection range to create a barrier between the Ligado cellular network and GPS, and Dessey believes that the level of protection is not to prevent interference from GPS signals. .
"This includes a 23 MHz protection range that protects the L1 GPS receiver in the Ligado terrestrial network, and a GPS receiver designed to receive signals from space regardless of the protection measures taken," said Desi.
“Despite this protection, many types of GPS receivers will remain subject to interference, and the GPS contains a portion of the satellite satellite that sends wireless signals to users. This means that L1 GPS receivers are designed to interfere, but they will not tolerate With space systems in the adjacent spectrum the interference from Earth systems in adjacent frequency bands. "
The Ministry of Defense media said that the results of the federal agency tests indicate that the FCC requirements will not prevent these impacts on millions of GPS receivers in the United States, and a large number of complaints are expected.
Congress should review the FCC decision, as Senator James Enhoff said: "I don't think it is a good idea to give up GPS signals because GPS signals benefit our country and the economic security of the company and the interests of investors."
"It could jeopardize our willingness to fight and our military capabilities, and manipulation of the global positioning system will harm the entire US economy," he added.
FCC response:
A spokesman for the Chairman of the Federal Communications Commission (Ajitbay) described the military's concerns as "baseless concerns."
(The FCC) said: "The Defense Department's measure of harmful interference does not measure harmful interference, and the energy level of the tests that are based on it is much higher than that approved by the (FCC)."
The Federal Agency added that the Ministry of Defense received the draft last fall, and Legado said it was making great efforts to prevent disruption and would repair or replace any government agency considered vulnerable to harmful interference, but to pay the price.
Energy limits:
Bey said that in addition to the protection range, the FCC also imposed a 9.8 dB power limit on Legado's operation of signals entering the Earth. “This limit is 99% less than the company's proposal for 2015.”
However, Daisy said that this decrease does not match the energy level near the L1 GPS signal examined by the Ministry of Transport.
Disi also criticized the coordination plan, saying it was insufficient to protect many military and civilian GPS devices, and said federal, industrial and regular consumers were using millions of portable GPS receivers.
He said: "Given the size, there is no way to protect these mobile phone operations, and most GPS users will never know whether Ligado has disabled their device or has reported this most serious challenge on this issue."
The Federal Communications Commission (FCC) clarified that Ligado's coordination plan required site reporting and technical operational standards for its base stations to potentially affected stakeholders before commissioning, monitoring the performance of base station site transfers, established procedures, and responses to trusted crash reports. , Including quick stops if necessary.
Although the FCC hopes the U.S. government will protect the Ligado GPS receivers and repair or replace devices that prove to be harmful at its own expense, this does not take into account the secret nature and extent of military use of the global positioning system. A large number of government beneficiaries and affected military platforms.
It should be noted that the signals received from the GPS satellites are very weak, as is the case with all satellites. GPS receivers on the ground must be very sensitive to use, so they maintain a dedicated frequency range, and transmitters operate near this range. The frequency assigned to the GPS system darkens its signal.