3G - MIMO

[sad_RNP]

Dear

in 3G network , is MIMO really used ?

or MIMO used actually in 4G



thanks for your support

[khurrambilal01]

Dear

in 3G network , is MIMO really used ?

or MIMO used actually in 4G



thanks for your support


MIMO is used in 3G but very rare Networks use MIMO for 3G because of unavailability of MIMO in 3G handsets.
MIMO is default function for LTE so all handsets of LTE support this feature.

[yafawi79]

I think MIMO is used only in case of HSDPA+ where two frequenies transmitted at same time to achive 28 or 21 Mbps(anchor carrier + suplemmentry carrier). Thanks

[khurrambilal01]

I think MIMO is used only in case of HSDPA+ where two frequenies transmitted at same time to achive 28 or 21 Mbps(anchor carrier + suplemmentry carrier). Thanks

MIMO has nothing to do with two frequencies it just improves the UE reception with same radio conditions because now we have two antennas so we have 2 TX and 2 Rx :)

UE also has 2 TX and NodeB also has 2 TX which means DL/UL reception has imrpoved.

the two frequency case you are talking about is DC not MMO.

[Philippe]

MIMO has nothing to do with two frequencies it just improves the UE reception with same radio conditions because now we have two antennas so we have 2 TX and 2 Rx :)

UE also has 2 TX and NodeB also has 2 TX which means DL/UL reception has imrpoved.

the two frequency case you are talking about is DC not MMO.

I agree. I would also say that Dual Carrier (DC) is more efficient than MIMO in macrocell networks. In macrocell typical environment, MIMO will only improve performances in good radio conditions so typically 20%-30% average cell throughput improvement and no improvement at cell edge. While Dual Carrier will imporve performances everywhere and so also at cell edge.

[firstmaxim]

MIMO was introduced in R7 of UMTS. You can see operators, implement HSPA+ which is based on WCDMA RAT with either the MIMO or 16 QAM option.
R8 LTE implements 2x2 MIMO, although 4x4 MIMO is also specified in the standard. R10 LTE (LTE Advanced) supports even 8X8 MIMO.