An enhanced spread-spectrum uplink technique provides more efficient packet transfer in a wireless network. A mobile station requests to utilize an uplink channel, typically, a physical dedicated channel. If the network will grant access, a base station sends back a channel-request-granted message, which specifies a transmission start time and length. The base station starts related downlink transmissions at the start time, and at a time thereafter, the mobile station starts sending packet data over the uplink physical dedicated channel. After a transmission of no more that the specified length, the mobile station ceases its uplink transmission on the dedicated channel, and the base station and/or the mobile station can immediately release one or more channel resources. The grant message and/or the subsequent signaling communications from the base station may also specify a modulation scheme and a channelization code for the uplink channel.