The state of the Washington federal regulatory and legislative communications world will change dramatically as a result of the elections.

Federal Communications Commission Chairman Charles Ferris, a former Democratic congressional staffer, is certain to be replaced by a Reagan-appointed nominee.

Ferris said yesterday he has not decided whether to remain on the commission as a member. His term expires in 1984. There is a lame-duck seat on the commission, and Reagan upon taking office could immediately name a new chairman to the FCC from outside the commission's current ranks.

In one congressional upset, Rep. Lionel Van Deerlin (D-Calif.), chairman of the House communications subcommittee and the principal author of a controversial bill to revamp the nation's telephone industry, lost to Republican Duncan Hunter in Californi's 23rd District.

Observers attributed the loss to Hunter's aggressive campaign against Van Deerlin's defense record and partly to a Hunter mailing that suggested consumer telephone bills might rise by five times if the Van Deerin legislation were enacted.

Van Deerlin, a nine-term member of the House, once had a 30-point lead over Hunter, according to the San Diego Democrat's own polls. Van Deerlin was an outspoken supporter of President Carter and was the second member of the California House delegation to endorse Carter. "I'm not going to blame anyone else for my defeat," Van Deerlin said.

He told a press conference yesterday that the communications rewrite legislation is "a good sound piece of legistion" and that the bill would be around during the next Congress. Van Deerlin also said he would not take a job with a large communications company upon leaving the House.

Rep. Timoty Wirth (D-Colo.), another leader in the communications bill fight, may be headed for the subcommittee chairman slot, although Rep. John Dingell (D-Mich.), the incoming chairman of the full Commerce committee, has suggested a possible revamping of the subcommittee structure.

On the Senate side, where Democrats are turning over control to Republicans, the Senate communications subcommittee presumably will be turned over to Sen. Barry Goldwater (R-Ariz.), subcommittee ranking minority member, if he maintains his narrow lead over a Democratic challenger. mIf not, some observers say Sen. Harrison Schmitt (R-N.M.) may take the post.