comm.LTEMIMOChannel
(Removed) Filter input signal through LTE MIMO multipath fading channel
comm.LTEMIMOChannel
has been. Use comm.MIMOChannel
instead. For information on updating your code, see Version History.
Description
The comm.LTEMIMOChannel
System object™ filters an input signal through an LTE multiple-input multiple-output
(MIMO) multipath fading channel.
A specialization of the comm.MIMOChannel
System object, the comm.LTEMIMOChannel
System objects
offers pre-set configurations for use with LTE link level simulations. In addition to
the comm.MIMOChannel
System object, the comm.LTEMIMOChannel
System object also corrects the correlation matrix to be positive semi-definite, after
rounding to 4-digit precision. This System object models Rayleigh fading for each of its links.
To filter an input signal using an LTE MIMO multipath fading channel:
Define and set up your LTE MIMO multipath fading channel object. See Construction.
Call
step
to filter the input signal using an LTE MIMO multipath fading channel according to the properties ofcomm.LTEMIMOChannel
. The behavior ofstep
is specific to each object in the toolbox.
Note
Starting in R2016b, instead of using the step
method to perform the operation defined by the System object, you can call the object with arguments, as if it were a function. For
example, y = step(obj,x)
and y = obj(x)
perform equivalent operations.
Construction
H = comm.LTEMIMOChannel
creates a 3GPP Long Term Evolution (LTE)
Release 10 specified multiple-input multiple-output (MIMO) multipath fading channel
System object, H
. This object filters a real or complex input
signal through the multipath LTE MIMO channel to obtain the channel impaired
signal.
H = comm.LTEMIMOChannel(Name,Value)
creates an LTE MIMO multipath
fading channel object, H
, with the specified property
Name
set to the specified Value
. You can
specify additional name-value pair arguments in any order as
(Name1
,Value1
,...,NameN
,ValueN
).
Properties
|
Input signal sample rate (Hertz) Specify the sample rate of the input signal in hertz as a
double-precision, real, positive scalar. The default value of this property
is |
|
Channel propagation profile Specify the propagation conditions of the LTE multipath fading channel as
one of This property defines the delay profile of the channel to be one of EPA, EVA, and ETU. This property also defines the maximum Doppler shift of the channel to be 5 Hz, 70 Hz, or 300 Hz. The Doppler spectrum always has a Jakes shape in the LTE specification. The EPA profile has seven paths. The EVA and ETU profiles have nine paths. The following tables list the delay and relative power per path associated with each profile.
|
|
Antenna configuration Specify the antenna configuration of the LTE MIMO channel as one of
The property value is in the format of Nt-by-Nr. Nt represents the number of transmit antennas and Nr represents the number of receive antennas. |
|
Spatial correlation strength Specify the spatial correlation strength of the LTE MIMO channel as one of
The transmit and receive spatial correlation matrices are defined from this property according to the LTE specification Release 10. See the Algorithms section for more information. |
|
Antenna selection Specify the antenna selection scheme as one of |
|
Source of random number stream Specify the source of random number stream as one of |
|
Initial seed of mt19937ar random number stream Specify the initial seed of an mt19937ar random number generator algorithm
as a double-precision, real, nonnegative integer scalar. The default value
of this property is |
|
Normalize path gains (logical) Set this property to |
|
Normalize channel outputs (logical) Set this property to |
|
Enable path gain output (logical) Set this property to |
Methods
reset | (Removed) Reset states of the LTEMIMOChannel
object |
step | (Removed) Filter input signal through LTE MIMO multipath fading channel |
Common to All System Objects | |
---|---|
release | Allow System object property value changes |
Examples
Algorithms
This System object is a specialized implementation of the comm.MIMOChannel
System object. For additional algorithm information, see the comm.MIMOChannel
System object help page.
Spatial Correlation Matrices
The following table defines the transmitter eNodeB correlation matrix.
One Antenna | Two Antennas | Four Antennas | |
---|---|---|---|
eNodeB Correlation | ReNB = 1 |
|
|
The following table defines the receiver UE correlation matrix.
One Antenna | Two Antennas | Four Antennas | |
---|---|---|---|
UE Correlation | RUE = 1 |
|
|
The following table describes the Rspat channel spatial correlation matrix between the transmitter and receiver antennas.
Tx-by-Rx Configuration | Correlation Matrix |
---|---|
1-by-2 |
|
2-by-2 |
|
4-by-2 |
|
4-by-4 |
|
Spatial Correlation Correction
Low Correlation | Medium Correlation | High Correlation | |||
---|---|---|---|---|---|
α | β | α | β | α | β |
0 | 0 | 0.3 | 0.9 | 0.9 | 0.9 |
To insure the correlation matrix is positive semi-definite after round-off to 4 digit precision, this System object uses the following equation:
Where
α represents the scaling factor such that the smallest value is used to obtain a positive semi-definite result.
For the 4-by-2 high correlation case, α=0.00010.
For the 4-by-4 high correlation case, α=0.00012.
The object uses the same method to adjust the 4-by-4 medium correlation matrix to insure the correlation matrix is positive semi-definite after rounding to 4 digit precision with α = 0.00012.
Selected Bibliography
[1] 3rd Generation Partnership Project, Technical Specification Group Radio Access Network, Evolved Universal Terrestrial Radio Access (E-UTRA), Base Station (BS) radio transmission and reception, Release 10, 2009–2010, 3GPP TS 36.104, Vol. 10.0.0.
[2] 3rd Generation Partnership Project, Technical Specification Group Radio Access Network, Evolved Universal Terrestrial Radio Access (E-UTRA), User Equipment (UE) radio transmission and reception, Release 10, 2010, 3GPP TS 36.101, Vol. 10.0.0.
[3] Oestges, C., and B. Clerckx. MIMO Wireless Communications: From Real-World Propagation to Space-Time Code Design, Academic Press, 2007.
[4] Correira, L. M. Mobile Broadband Multimedia Networks: Techniques, Models and Tools for 4G, Academic Press, 2006.
[5] Jeruchim, M., P. Balaban, and K. S. Shanmugan. Simulation of Communication Systems, Second Edition, New York, Kluwer Academic/Plenum, 2000.