Main Content

evdoReverseWaveformGenerator

Generate 1xEV-DO reverse link waveform

Description

example

waveform = evdoReverseWaveformGenerator(cfg) returns the 1xEV-DO reverse link waveform as defined by the parameter configuration structure, cfg.

The top-level parameters and lower-level substructures of cfg specify the waveform and channel properties used by the function to generate a 1xEV-DO waveform. You can generate cfg by using the evdoReverseReferenceChannels function.

Note

The tables herein list the allowable values for the top-level parameters and substructure fields. However, not all parameter combinations are supported. To ensure that the input argument is valid, use the evdoReverseReferenceChannels function. If you input the structure fields manually, consult [1] to ensure that the input parameter combinations are permitted.

Examples

collapse all

Create a structure to generate a Release 0, 1xEV-DO waveform having a 19.2 kbps data rate.

config = evdoReverseReferenceChannels('Rel0-19200');

Verify that the packet has a data rate of 19.2 kbps.

config.PacketSequence.DataRate
ans = 19200

Generate the complex waveform.

wv = evdoReverseWaveformGenerator(config);

Create a structure to generate four packets of a Revision A channel having 768-bit packets transmitted over eight slots.

config = evdoReverseReferenceChannels("RevA-768-8",4);

Calculate the sample rate of the waveform.

fs = 1.2288e6 * config.OversamplingRatio;

Disable the internal filter of the evdoReverseWaveformGenerator. Generate the 1xEV-DO waveform.

config.FilterType = "off";
wv = evdoReverseWaveformGenerator(config);

sa = spectrumAnalyzer( ...
    SampleRate=fs, ...
    ChannelNames=["1xEV-DO","1xEV-DO filtered"]);

Create a lowpass FIR filter with a 500 kHz passband, a 750 kHz stopband, and a stopband attenuation of 60 dB.

d = designfilt("lowpassfir", ...
    PassbandFrequency=500e3, ...
    StopbandFrequency=750e3, ...
    StopbandAttenuation=60, ...
    SampleRate=fs);

Change the filter type to "Custom" and specify the coefficients from the digital filter, d.

config.FilterType = "Custom";
config.CustomFilterCoefficients = d.Coefficients;

Generate the waveform using the custom filter coefficients.

filtwv = evdoReverseWaveformGenerator(config);

Plot the spectrum of the unfiltered and filtered 1xEV-DO waveform. The filter attenuates the waveform by 60 dB for frequencies outside of ± 750 kHz.

sa(wv,filtwv)
release(sa)

Input Arguments

collapse all

Configuration of the parameters and channels used by the waveform generator. The configuration structure is defined in these tables.

Top-Level Parameters and Substructures

Parameter Field

Values

Description

Release'Release0' | 'RevisionA'

1xEV-DO applicable standard

LongCodeMaskI

42-bit binary number

Long code identifier for in-phase channel

LongCodeMaskQ

42-bit binary number

Long code identifier for quadrature channel

NumChips

Positive scalar integer

Number of chips in the waveform

OversamplingRatio

Positive scalar integer

Oversampling ratio at output

FilterType'cdma2000Long' | 'cdma2000Short' | 'Custom' | 'Off'

Specify the filter type or disable filtering

CustomFilterCoefficients

Real vector

Custom filter coefficients (applies when FilterType is set to 'Custom')

InvertQ'Off' | 'On'

Negate the quadrature output

EnableModulation'Off' | 'On'

Enable carrier modulation

ModulationFrequency

Nonnegative scalar integer

Carrier modulation frequency (applies when EnableModulation is 'On')

ACKChannel

Structure

See ACKChannel substructure.
PilotChannel

Structure

See PilotChannel substructure.
AuxPilotChannel

Not present or structure

See AuxPilotChannel substructure.
PacketSequence

Structure

See PacketSequence substructure.

ACKChannel Substructure

Include the ACKChannel substructure in the cfg structure to specify the acknowledgment channel. The ACKChannel substructure contains these fields.

Parameter Fields

Values

Description

Enable'On' | 'Off'

Character vector to enable or disable the channel

Power

Real scalar

Channel power (dBW)

DataSource

Cell array, {'PN Type', RN Seed} or binary vector.

Standard PN sequence options are 'PN9', 'PN15', 'PN23', 'PN9-ITU', and 'PN11'.

Data source. Specify a standard PN sequence with a random number seed or a custom vector.

PilotChannel Substructure

Include the PilotChannel substructure in the cfg structure to specify the pilot channel. The PilotChannel substructure contains these fields.

Parameter Fields

Values

Description

Enable'On' | 'Off'

Character vector to enable or disable the channel

Power

Real scalar

Channel power (dBW)

DataSource

Cell array, {'PN Type', RN Seed} or binary vector.

Standard PN sequence options are 'PN9', 'PN15', 'PN23', 'PN9-ITU', and 'PN11'.

Data source. Specify a standard PN sequence with a random number seed or a custom vector.

EnableCoding'On' | 'Off'

Enable channel coding

AuxPilotChannel Substructure

Include the AuxPilotChannel substructure in the cfg structure to specify the auxiliary pilot channel, which is available only for Revision A. The AuxPilotChannel substructure contains these fields.

Parameter Fields

Values

Description

Enable'On' | 'Off'

Character vector to enable or disable the channel

Power

Real scalar

Channel power (dBW)

DataSource

Cell array, {'PN Type', RN Seed} or binary vector.

Standard PN sequence options are 'PN9', 'PN15', 'PN23', 'PN9-ITU', and 'PN11'.

Data source. Specify a standard PN sequence with a random number seed or a custom vector.

EnableCoding'On' | 'Off'

Enable channel coding

PacketSequence Substructure

Include the PacketSequence substructure in the cfg structure to define a sequence of data packets for consecutive transmission. The PacketSequence substructure contains these fields.

Parameter Field

Values

Description

Power

Real scalar

MAC index associated with the packet

EnableCoding'Off' | 'On'

Enable error correction coding

DataSource

Cell array, {'PN Type', RN Seed} or binary vector.

Standard PN sequence options are 'PN9', 'PN15', 'PN23', 'PN9-ITU', and 'PN11'.

Data source. Specify a standard PN sequence with a random number seed or a custom vector.

Release 0
DataRate9600 | 19200 | 38400 | 76800 | 153600

Data rate (bps)

Revision A
PacketSize128 | 256 | 512 | 768 | 1024 | 1536 | 2048 | 3072 | 4096 | 6144 | 8192 | 12288

Packet size (bits)

NumSlots4 | 8 | 12 | 16

Number of slots

Output Arguments

collapse all

Modulated baseband waveform comprising the 1xEV-DO physical channels, returned as a complex vector array.

References

[1] 3GPP2 C.S0024–A v3.0. “cdma2000 High Rate Packet Data Air Interface Specification.” 3rd Generation Partnership Project 2.

Version History

Introduced in R2015b