Hello experts.
From the user perspective, what are main advantages of MIMO and CA in LTE?
I want to explain it in an easy way…
2 Likes
You can start imagining a highway facing traffic congestion.
So, you may add more lanes (taking up new land) to the highway sideways to fit more cars.
That’s CA – CARRIER AGGREGATION!
Continuing, imagine there are no more lands to buy and build new lanes. For example, because there are houses on either way of the highway. Then you must build additional decks upwards.
That’s MIMO!
2 Likes
Which one will be better option MIMO or Carrier Aggregation?
Definitely Carrier Aggregation
CA for providing better Quality of Service…
It help to minimise the tradeoff between Coverage and Capacity
1 Like
Your analogy is perfect, congratulations.
Only note that CA is a separate thoroughfare directly adjacent to the existing thoroughfare.
Adding lanes is analogous to widening the LTE carrier.
Perfect example with the additional road decks for MIMO.
Shouldn’t it be like this
If CA is possible…Then obviously implement CA…
Then go for MIMO with CA…
It is more like : Single Carrier < 2 carriers < 2 carriers with MIMO < Massive MIMO
i.e. Massive MIMO is better than 2 carriers with MIMO which is better than 2 Carriers which is better than a single carrier
In case of carrier aggregation if we are adding 5MHz to existing 5MHz is there any change in existing antenna is required?
No…Same antenna radiates on a different PCI…
In case of MIMO?
A 4 port antenna is good enough for CA + MIMO…4t4r
What about 2T+2R?
See 2t2r or 2t4r or 4t4r is a radio functionality
Is 2T+2R required for MIMO? Is 2T+2R required for CA? Is 2T+2R not suffice for CA+MIMO? Please clarify.
2t2r MIMO radio has 2 ports…So a 2 port antenna is good enough…
The True sense MIMO is 4T4R…Where u use 4 radio ports and 4 antenna ports … and benefit from receive and transmit diversity
1 Like
Ok. Thank you 
1 Like
Carrier Aggregation (CA) and MIMO has the same goal.
It is to transmit the multiple data streams parallaly to achieve high data throughputs.
→ Difference between CA & MIMO: there is a another way of simultaneous Throughputs of multiple data streams called CoMP (COORDINATE MULTIPLE POINT OPERATOR)
- Increase spectral efficiency.
- Reduce interference.
- Increase Throughputs.
So, what’s actually?
- MIMO: Transmission of the multiple data streams with ONE ENB Via same frequency.
- CA: Transmission of multiple data streams using multiple ENB’s with each ENB Having different frequencies.
Note : Most of the case, CA &MIMO are used at the same time!
CA : We are using different frequencies (we need at least two different frequencies)
MIMO : We are using just on frequency with at least 2rank (2 independent channels)
Specific UE cannot used both of them at the same time
