Multihop techniques in CDMA (Code Division Multiple Access) radio access networks, enable dead-spot mobile stations, which cannot communicate with base stations directly, to send packets to them via other mobile stations. However, there are several requirements to apply the multihop techniques to ongoing third generation radio access networks. That is, infrastructure networks should not be changed and modifications to software and hardware of mobile stations should be minimized. Unfortunately, the conventionally proposed methods do not satisfy these requirements. In this paper, we propose a mechanism for establishing connections and relaying packets between mobile stations. In this mechanism, the mobile stations are connected to one another and relay data through a random access channel, which is an uplink common channel. In addition, it satisfies the requirements for applying multihop techniques to third generation radio access networks, which are based on CDMA/FDD (Frequency Division Duplex). Moreover, we also discuss our evaluation of the performance of the mechanism through computer simulations. The results we obtained reveal that it is capable of reducing dead-spot mobile stations and improving throughput with only limited modifications to conventional systems.