DC-HSPA is - I think - only in Release 8 version at the moment Mr I - all is does is to double the data rates by doubling the bandwidth to 10 MHz (2×5 MHz).
In theory, DC-HSDPA can support up to 42.2 Mbps, but unlike HSPA, it does not need to rely on MIMO transmission. This is the key.
My understandng is that Release 8 of DC-HSDPA can only operate on adjacent carriers, whilst Release 9 will allow the paired cells to operate on two different frequency bands. I was talking to a Three tech recently who said the carrier is testing Quad Channel - QC-HSPA!
Obviously the spread spectrum nature of 3G / DC-HSPA in this context will result in packet quality degradation, but since it's one handset and one cell site controlling everything, it's not a MAJOR problem.
What I was trying to say - sorry I didn't express myself clearly - is that two 3G transceivers placed side by side would hit packet quality problems - and since we're talking about handsets that are designed cheaply and based on older chip sets, having one 3G and one 2G transceiver in the same handset avoids any problems - and it's cheaper
+Steve
[size=2]Steve Gold
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