APCO Tentatively Backs LMCC's 800 MHz Interference Proposal; MRA Cites Objection

interstitial channels (12.5 kHz spacing) adjacent to 'standard' (25 kHz spacing) stations operating with various modulation types." APCO said it appreciated the LMCC efforts and believes the "proposed contours can be workable" but said they're untested. "We would encourage manufacturers to submit test reports into the record to verify that no interference would result from new interstitial operations," APCO said. "As noted by the Public Safety Communications Council (of which APCO is a member), APCO would support use of tile-based matrix studies using TSB-88 methods when the proposed operations of a public safety applicant fail a contour analysis. APCO supports the proposed interference contours consistent with the comments herein." Mobile Relay Associates said it supported most of the LMCC proposal but said one part of it was inconsistent with the rest of the proposal and decades of public policy. "That one portion of the LMCC proposal is its proposed treatment of instances where there is absolutely no spectral overlap between the incumbent station and the proposed station," MRA said. "Neither the Commission nor the LMCC has ever required an interference analysis when there is a complete absence of spectral overlap, and, as to very narrowband 4 kHz emissions in particular, there is a plethora of real-world experience proving that interference to incumbent stations does not exist in the absence of spectral overlap."