A novel wireless multimedia network employing a time division duplex C
DMA/TDMA scheme is proposed. The network connects mobile multimedia te
rminals to an ATM based LAN through a radio central unit, and provides
both uplink and downlink with unbalanced data rates in the same frequ
ency band. The uplink (from a mobile terminal to a radio central unit)
employs a CDMA scheme to transmit low speed human interface signals (
-2.4 kbit/s), and the downlink employs a TDMA scheme to transmit high
speed video signals (-24 Mbit/s). The data rates of both links are ind
ependent from that of the LAN. The uplink also employs a RAKE receiver
and a forward error correction (FEC) scheme using a BCH code in order
to reduce bit errors caused by multipath fading. To mitigate channel
degradation caused by the near-far problem and multipath fading, a tra
nsmission power control (TPC) method for both links and a channel equa
lizer (CEQ) for the downlink are proposed. The control signals for the
TPC and the CEQ are estimated from the impulse response of the channe
l which is extracted as the output of the matched filters in the CDMA
receiver. Theoretical analyses are performed to evaluate the bit error
rate (BER) characteristics of the proposed network. The EER performan
ce is derived for a general multipath fading condition modeled by the
Nakagami-m distribution and a typical delay profile. Numerical calcula
tion using recent propagation measurements shows the bit error rates o
f both uplink and downlink to be less than 10(-6) when both of the TPC
and the CEQ are employed if there are some specular components in the
received signals. This excellent performance can cut a way to realize
a mobile multimedia terminal for customer premises. Furthermore, the
configuration of the mobile terminal is quite simple even if the high
speed TDMA signals are received over a multipath fading channel.