comm.OSTBCCombiner
Combine inputs using orthogonal space-time block code
Description
The comm.OSTBCCombiner
System object™ combines the input signal (from all of the receive antennas) and the channel
estimate signal to extract the soft information of the symbols encoded by an orthogonal
space-time block code (OSTBC). The input channel estimate does not need to be constant and can
vary each time you run the object. The combining algorithm uses only the estimate for the
first symbol period per codeword block. A multiple-input multiple-output (MIMO) communications
system applies symbol demodulation or decoding after the OSTBC combining process.
To combine an input symbol sequence using OSTBC:
Create the
comm.OSTBCCombiner
object and set its properties.Call the object with arguments, as if it were a function.
To learn more about how System objects work, see What Are System Objects?
Creation
Syntax
Description
ostbccomb = comm.OSTBCCombiner
creates an OSTBC combiner System
object, ostbccomb
. This object combines the input signal (from all of
the receive antennas) with the channel estimate signal to extract the soft information of
the symbols encoded by an OSTBC.
ostbccomb = comm.OSTBCCombiner(N,M)
creates an OSTBC combiner
object with the NumTransmitAntennas
property set to N
and the NumReceiveAntennas
property set to M
.
ostbccomb = comm.OSTBCCombiner(___,
creates an OSTBC combiner object using any of the previous syntaxes and sets properties using one or more name-value arguments. For example,
Name
=Value
)SymbolRate=1/2
sets the symbol rate of the code to
1/2
.
Properties
Usage
Syntax
Description
Input Arguments
Output Arguments
Object Functions
To use an object function, specify the
System object as the first input argument. For
example, to release system resources of a System object named obj
, use
this syntax:
release(obj)
Examples
Algorithms
The OSTBC combiner supports five different OSTBC combining computation algorithms.
Depending on the selection for SymbolRate
and
NumTransmitAntennas
, you can select one of the algorithms shown in this
table.
Transmit Antenna | Rate | Computational Algorithm per Codeword Block Length |
---|---|---|
2 | 1 |
|
3 | 1/2 |
|
3 | 3/4 |
|
4 | 1/2 |
|
4 | 3/4 |
|
represents the estimated kth
symbol in the OSTBC codeword matrix. hij represents
the estimate for the channel from the ith
transmit antenna and the jth receive antenna.
Values for i are in the range [1
, N],
where N is the number of transmit antennas. Values for j
are in the range [1
, M], where M is
the number of receive antennas. rlj represents the
lth symbol at the
jth receive antenna per codeword block. The
value of l can range from 1 to the codeword block length. represents the summation of channel power per link, that is
Extended Capabilities
Version History
Introduced in R2012a