Following are the reverse link features of CDMA 2000:

a) Channels are primarily code multiplexed

b) Separate channels are used for different QoS and physical layer characteristics

c) Transmission is continuous to avoid EMI (Electro-magnetic interference)

d) Channels are orthogonalized by Walsh functions and I/Q split so that performance is equivalent to BPSK

e) Hybrid combination of QPSK and BPSK modulation

f) Coherent reverse link with continuous pilot

g) Forward power control information is time-multiplexed with the pilot By restricting alternate phase changes of the complex scrambling, power peaking is reduced and side lobes are narrowed

h) Forward error correction:

• Convolutional codes (k=9) are used for voice and data
• Parallel turbo codes (k= 4) are used for high data rates on supplemental channels

i) Fast reverse power control: 800 times per second Frame lengths

• 20-ms frames are used for signaling and user information
• 5-ms frames are used for control information

j) physical channels (PHCH) used by CDMA 2000 for Reverse link are

• Pilot (R-PICH)* channel
• Access (R-ACH)
• Dedicated Control (R-DCCH)* channel
• Fundamental (R-FCH)
• Common Control (R-CCH) channel
• Enhanced Access (R-EACH)*