WASHINGTON-Letters exchanged between lawyers for the Baltimore Mass Transit Administration and Bethesda, Md.-based American Personal Communications apparently have addressed all problems related to two interference incidents in Baltimore, including any slowing of incumbent microwave user relocation negotiations between the two parties.
In a Dec. 27 letter from Maryland Assistant Attorney General Kathleen Masterton to APC attorney Margaret Ruggieri, Masterton outlined two separate instances in which an APC personal communications services transmitter located on Druid Hill in Baltimore interfered with MTA’s 2 GHz microwave links that feed the city’s Metro transit system, MARC railroad service, Light Rail and bus service, and freight trains operating along Baltimore’s rights of way. In addition, Masterton wrote that MTA police communications had been compromised, “with potentially devastating consequences to the public and to officers cut off from radio communications and potential back-up assistance.”
Masterton wrote that microwave communications were disrupted in October and November to such an extent “that our communications links were rerouted to telephone lines to restore communications capabilities.” Problems included high bit-error rates and dropped service.
“Sadly, the Federal Communications Commission’s hope that PCS providers would responsibly respect the rights of incumbent users has been shown to be unfounded,” Masterton concluded. She asked APC to reimburse all costs incurred by MTA related to the problems, including attorney fees, as part of any relocation contract that is signed between the two or as a separate payment if such negotiations fall through.
In his Jan. 3 response, APC counsel Kurt Wimmer of the Washington, D.C. firm of Covington & Burling, countered that several notifications were sent by APC to MTA from March 1991 to March 1995 regarding APC’s experimental and commercial PCS endeavors-including a formal frequency-coordination notice-and that MTA did not respond to any of them. “Before Oct. 24, 1995, APC had no complaints of interference from MTA or any other incumbent microwave user during its more than five years of experimental and preoperational transmissions,” Wimmer wrote.
In addition, Wimmer pointed out that APC was not notified by MTA of any interference in October until nine days after the problem first was reported; APC engineers, Wimmer wrote, solved the problem the following morning. It took six days to remedy the November interference, Wimmer said, because MTA personnel were on Thanksgiving leave.
Upon further investigation, APC engineers found that MTA was operating its two microwave links “at significantly lower power than its FCC license indicates, rendering its path much more susceptible to interference. Had MTA been operating at the power designated*…*or if MTA had disclosed its actual power by responding to APC’s frequency-coordination letters, this interference would not have occurred.”
MTA is releasing no further comment on this matter. No interference from APC transmitters to Washington, D.C.-area microwave incumbents has been reported.