where RC and Rb are chip rate and channel bit rate, respectively. ch_os denotes the channel-over-sampling factor. Setting total_signal_power to 1, Eb/No becomes:
where is the received power spectral density of the downlink as measured at the UE antenna connector, Ioc is the power spectral density of a band-limited white noise source as measured at the UE antenna connector, Ior is the total transmit power spectral density of the downlink at the node B antenna connector, DPCH_Ec is the average energy per chip for DPCH, and . Assume no path loss.
Code orthoganality is assumed.