Create non-HT configuration object
The wlanNonHTConfig object is a configuration object for the WLAN
non-high-throughput (non-HT) packet format.
cfgNonHT = wlanNonHTConfig
cfgNonHT = wlanNonHTConfig(Name,Value)wlanNonHTConfig('Modulation','DSSS')
specifies the modulation type as direct-sequence spread spectrum (DSSS).
At runtime, the calling function validates object settings for properties relevant to the operation of the function.
Modulation — Modulation type for non-HT transmission'OFDM' (default) | 'DSSS' Modulation type for the non-HT transmission, specified as 'OFDM'
for orthogonal frequency division multiplexing (OFDM) or 'DSSS' for
direct-sequence spread spectrum (DSSS).
Data Types: char | string
ChannelBandwidth — Channel bandwidth of PPDU transmission'CBW20' (default) | 'CBW5' | 'CBW10' | 'CBW40' | 'CBW80' | 'CBW160'Channel bandwidth of PPDU transmission, specified as one of these values.
'CBW5' — Channel bandwidth of 5 MHz
'CBW10' — Channel bandwidth of 10 MHz
'CBW20' — Channel bandwidth of 20 MHz
'CBW40' — Channel bandwidth of 40 MHz for non-HT
duplicate
'CBW80' — Channel bandwidth of 80 MHz for non-HT
duplicate
'CBW160' — Channel bandwidth of 160 MHz for non-HT
duplicate
Data Types: char | string
InactiveSubchannels — Indicate inactive 20 MHz subchannels in non-HT duplicate packetfalse or 0 (default) | logical vectorIndicate inactive 20 MHz subchannels in a non-HT duplicate packet, specified as a
numeric or logical 0 (false) or a logical vector
with at least one element set to 0 (false). When
specifying a vector, the elements correspond to subchannels in order of increasing
absolute frequency. Each element indicates whether the corresponding 20 MHz subchannel
is inactive. To indicate an inactive 20 MHz subchannel, set the corresponding element to
1 (true). If you set this property to
0 (false), the wlanNonHTConfig
object applies that value to all 20 MHz subchannels, indicating that all subchannels are
active.
Example: [0 0 0 1] indicates a non-HT duplicate packet such that
the subchannel with the highest absolute frequency value is inactive.
To enable this property, set the ChannelBandwidth property to either 'CBW80' or
'CBW160'.
Data Types: logical
MCS — OFDM MCS used for transmission0 (default) | integer in the interval [0, 7]OFDM MCS used for transmission, specified as an integer in the interval [0, 7]. This
table shows the modulation type and coding rate for each valid value of
MCS.
Value of MCS | Modulation | Coding Rate | Coded Bits Per Subcarrier | Coded Bits Per OFDM Symbol | Data Bits Per OFDM Symbol | Data Rate in Mbps | ||
|---|---|---|---|---|---|---|---|---|
| 5-MHz Channel Bandwidth | 10-MHz Channel Bandwidth | 20-MHz Channel Bandwidth | ||||||
0 | Binary phase-shift keying (BPSK) | 1/2 | 1 | 48 | 24 | 1.5 | 3 | 6 |
1 | BPSK | 3/4 | 1 | 48 | 36 | 2.25 | 4.5 | 9 |
2 | quadrature phase-shift keying (QPSK) | 1/2 | 2 | 96 | 48 | 3 | 6 | 12 |
3 | QPSK | 3/4 | 2 | 96 | 72 | 4.5 | 9 | 18 |
4 | 16-point quadrature amplitude modulation (16-QAM) | 1/2 | 4 | 192 | 96 | 6 | 12 | 24 |
5 | 16-QAM | 3/4 | 4 | 192 | 144 | 9 | 18 | 36 |
6 | 64-QAM | 2/3 | 6 | 288 | 192 | 12 | 24 | 48 |
7 | 64-QAM | 3/4 | 6 | 288 | 216 | 13.5 | 27 | 54 |
For more information, see Table 17-4 of [1].
Data Types: double
DataRate — Data rate for DSSS modulation'1Mbps' (default) | '2Mbps' | '5.5Mbps' | '11Mbps'Data rate for DSSS modulation, specified as a one of these values:
'1Mbps' — Differential binary phase-shift keying
(DBPSK) with a data rate of 1 Mbps
'2Mbps' — Differential quadrature phase-shift keying
(DQPSK) with a data rate of 2 Mbps
'5.5Mbps' — Complementary code keying (CCK) with a
data rate of 5.5 Mbps
'11Mbps' — CCK with a data rate of 11 Mbps
Data Types: char | string
Preamble — DSSS modulation preamble type'Long' (default) | 'Short'DSSS modulation preamble type, specified as 'Long' or
'Short'.
The 'Short' value of this property does not apply when you set
the DataRate
property to '1Mbps'.
Data Types: char | string
LockedClocks — Clock locking indicator for DSSS modulationtrue or 1 (default) | false or 0Clock locking indicator for DSSS modulation, specified as a numeric or logical
1 (true) or 0
(false). This property corresponds to the locked clocks bit (bit
b2) of the SERVICE field as specified in Section 16.2.3.5 of [1]. To indicate that the physical
layer (PHY) implementation derives its transmit frequency clock and symbol clock from
the same oscillator, set this property to 1
(true). For more information, see Sections 16.2.3.5 and 18.1.3 of
[1].
Note
Section 18.3.2.2 of [1] specifies that the locked clocks bit must be 1 for all extended rate PHY (ERP) systems when transmitting at any of these rates:
An optional ERP-packet binary convolutional coding (ERP-PBCC) rate
A data rate described in Section 16 of [1]
Therefore, to model ERP systems, you must set this property to
1 (true).
Data Types: logical
PSDULength — PSDU length1000 (default) | integer in the interval [0, 4095]Physical layer convergence procedure (PLCP) service data unit (PSDU) length, in bytes, specified as an integer in the interval [0, 4095].
Data Types: double
NumTransmitAntennas — Number of transmit antennas1 (default) | positive integerNumber of transmit antennas, specified as a positive integer.
To enable this property, set the ChannelBandwidth property to 'CBW20'.
Data Types: double
CyclicShifts — Cyclic shift values of additional transmit antennas-75 (default) | integer in the interval [–200, 0] | row vectorCyclic shift values, in nanoseconds, of additional transmit antennas. The first
eight antennas use the cyclic shift values specified in Table 21-10 of [1]. The remaining
L antennas use the values you specify in this property, where L = NumTransmitAntennas –
8. Specify this property as one of these values:
An integer in the interval [–200, 0] – the wlanNonHTConfig object
uses this cyclic shift value for each of the L additional
antennas.
A row vector of length L of integers in the interval [–200,
0] – the wlanNonHTConfig object uses the kth
element as the cyclic shift value for the (k + 8)th transmit antenna.
Note
If you specify this property as a row vector of length greater than
L, the wlanNonHTConfig object uses only the
first L elements. For example, if you set the
NumTransmitAntennas property to 16,
the wlanNonHTConfig object uses only the first L= 16 – 8 = 8 elements of this vector.
To enable this property, set the NumTransmitAntennas property to a value greater than
8.
Data Types: double
SignalChannelBandwidth — Signal channel bandwidth in scrambler sequencefalse or 0 (default) | true or 1Signal channel bandwidth in the scrambler sequence, specified as a numeric or
logical 1 (true) or 0
(false). To signal the channel bandwidth, set this property to
1 (true). Otherwise, set this property to
0 (false). For more information, see section
17.3.5.5 of [1].
To enable this property, set the Modulation
property to 'OFDM'.
Data Types: logical
BandwidthOperation — Signal bandwidth operation in scrambler sequence'Absent' (default) | 'Static' | 'Dynamic'Signal bandwidth operation in the scrambler sequence, specified as one of these values.
'Absent' — Disable bandwidth operation
signaling
'Static' — Signal static bandwidth operation
'Dynamic' — Signal dynamic bandwidth
operation
For more information, see section 17.3.5.5 of [1].
Data Types: char | string
scramblerRange | Get scrambler initialization range |
Configure transmission parameters by creating a wlanNonHTConfig object, specifying a channel bandwidth of 80 MHz and static bandwidth operation.
cfg = wlanNonHTConfig('ChannelBandwidth','CBW80','SignalChannelBandwidth',true, ... 'BandwidthOperation','Static');
Generate a random PSDU of the appropriate length.
psdu = randi([0 1],8*cfg.PSDULength,1,'int8');Generate the initial pseudorandom scrambler sequence.
[range,numBits] = scramblerRange(cfg); scramInit = randi(range);
Generate the non-HT Data field signal.
y = wlanNonHTData(psdu,cfg,scramInit);
Create a wlanNonHTConfig object for DSSS operation for a PSDU length of 2048 bytes.
cfgNHT = wlanNonHTConfig('Modulation','DSSS','PSDULength',2048)
cfgNHT =
wlanNonHTConfig with properties:
Modulation: 'DSSS'
DataRate: '1Mbps'
LockedClocks: 1
PSDULength: 2048
Section 17 of [1] specifies OFDM PLCP 5 MHz, 10 MHz, and 20 MHz channel bandwidth operation.
Timing parameters associated with the OFDM PLCP are listed in this table:[1] .
| Parameter | Value | 20 MHz Channel Bandwidth | 10 MHz Channel Bandwidth | 5 MHz Channel Bandwidth |
|---|---|---|---|---|
NSD: Number of data subcarriers | 48 | 48 | 48 | 48 |
NSP: Number of pilot subcarriers | 4 | 4 | 4 | 4 |
NST: Total number of subcarriers | NSD + NSP | 52 | 52 | 52 |
ΔF: Subcarrier frequency spacing, in MHz | (Channel bandwidth) / 64 | 0.3125 | 0.15625 | 0.078125 |
TFFT: Inverse Fast Fourier Transform (IFFT) / Fast Fourier Transform (FFT) period, in μs | 1 / ΔF | 3.2 | 6.4 | 12.8 |
TPREAMBLE: PLCP preamble duration, in μs | TSHORT + TLONG | 16 | 32 | 64 |
TSIGNAL: Duration of the L-SIG symbol, in μs | TGI + TFFT | 4 | 8 | 16 |
TGI: GI duration, in μs | TFFT/4 | 0.8 | 1.6 | 3.2 |
TGI2: Training symbol GI duration, in | TFFT/2 | 1.6 | 3.2 | 6.4 |
TSYM: Symbol interval, in μs | TGI + TFFT | 4 | 8 | 16 |
TSHORT: L-STF duration, in μs | 10 × TFFT /4 | 8 | 16 | 32 |
TLONG: L-LTF duration, in μs | TGI2 + 2 × TFFT | 8 | 16 | 32 |
|
Note The standard refers to operation at 10 MHz as “half-clocked” and operation at 5 MHz as “quarter-clocked”. | ||||
The physical layer (PHY) protocol data unit (PPDU) is the complete physical layer convergence procedure (PLCP) frame, including PLCP headers, MAC headers, the MAC data field, and the MAC and PLCP trailers.
[1] IEEE Std 802.11-2016 (Revision of IEEE Std 802.11-2012). “Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications.” IEEE Standard for Information technology — Telecommunications and information exchange between systems. Local and metropolitan area networks — Specific requirements.
wlanDMGConfig | wlanHEMUConfig | wlanHESUConfig | wlanHETBConfig | wlanHTConfig | wlanS1GConfig | wlanVHTConfig[1] IEEE Std 802.11-2016 Adapted and reprinted with permission from IEEE. Copyright IEEE 2016. All rights reserved.
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