Since conventional broadcast in manets wastes a lot of resources due to redundant rebroadcasts , contention and collision , several existing broadcast protocols were proposed to resolve these problems .

传统的广播方法因为重覆广播、竞争及碰撞等问题而浪费很多网路资源，所以已经有很多方法被提出来解决这些问题。

Even aficionados accept that the glory days are gone : political freedom and new technology means listeners have more choice now , while local rebroadcasts and internet streaming give foreign stations more hum for the hertz .

就连短波狂热者都承认短波的辉煌已不再：尽管当地重播和网络收听提高了国外电台收听率，但政治自由以及新技术意味着现在的听众有更多的选择。