FBR Capital analyst David Dixon said the Mobile World Congress provided evidence that software and architecture design changes are "exponentially" driving up spectrum reuse and he believes DISH Network's (DISH) window of opportunity to monetize its spectrum is closing. Also, based on regulatory checks at the industry event, he sees a greater likelihood of a merger of Sprint (S) and T-Mobile (TMUS), but said that even if such a hypothetical merger were to fall through he thinks a combination of DISH and T-Mobile is unlikely. Dixon keeps an Underperform rating and $44 price target on DISH shares.