ns3::NrLbtAccessManager class

Derived classes

class NrCat2LbtAccessManager

Class that implements the Cat2 LBT channel access manager algorithm.

class NrCat3LbtAccessManager

Class that implements the Cat2 LBT channel access manager algorithm.

class NrCat4LbtAccessManager

Class that implements the Cat2 LBT channel access manager algorithm.

Public functions

auto AssignStreams(int64_t stream) -> int64_t

auto GetDeferTime() const -> const Time& virtual

Gets default defer time that is used by LBT algorithm.

auto GetEdThreshold() const -> double

Returns the ED threshold that is used in LBT algorithm and for energy detection.

auto GetMcot() const -> const Time&

Gets the MCOT of the transmission opportunity that will be granted to the user of LBT CAM, depends on the priority class.

auto GetSlotTime() const -> const Time&

Gets the duration of the slot that is configured to be used by LBT.

void RequestAccess() override

Function used by the user of the CAM to request the channel access.

void SetAccessGrantedCallback(const AccessGrantedCallback& cb) override

Sets the callback function that will be called to notify that the channel access is granted, once that LBT algorithm finishes successfully.

void SetDeferTime(const Time& deferTime)

void SetEdThreshold(double edThreshold)

Set the ED threshold to be used in LBT algorithm and energy detection in dBm.

void SetMcot(const Time& mcot)

Sets the duration of the transmission opportunity that will be granted to the user of LBT CAM, depends on the priority class.

void SetNrGnbMac(Ptr<NrGnbMac> mac) override

Set MAC instance for this channel access manager.

void SetNrSpectrumPhy(Ptr<NrSpectrumPhy> spectrumPhy) override

Set spectrum phy instance for this channel access manager.

void SetSlotTime(const Time& slotTime)

Sets the duration of the slot to be used by the LBT algorithm for.

Protected functions

auto GetBackoffSlots() -> uint32_t pure virtual

Get the random number of backoff slots to be used in the current execution of the LBT algorithm during the backoff process.

auto GetCurrentBackoffCount(void) const -> uint32_t

auto GetLastTxopStartTime() const -> Time

Gets the last TXOP start time.

auto GetLbtState() const -> LbtState

Gets the current LBT state.

void NotifyAccessGranted()

Notify the registered callbacks that the access is granted.

void RequestAccessAfterBackoff()

Function is called after backoff process is done to grant the access to the CAM user.

void RequestAccessAfterDefer() virtual

Function is called when defer period is finished to check if the it is necessary to ener to extended CCA.

void SetGrant() virtual

Function that does various things: notifies the user of the granted access, updates variables that are necessary for handling the next channel access request.

void SetLbtState(LbtState state)

Sets the LBT state.

void TransitionFromBusy()

Used when the LBT state machine returns from the BUSY state.

void TransitionToBusy(Time duration) virtual

Channel is busy for the given duration.

Protected variables

std::vector<AccessDeniedCallback> m_accessDeniedCb

The list of registered callback for the notification of access denied event.

std::vector<AccessGrantedCallback> m_accessGrantedCb

The list of registered callacks for the channel access grant notification.

uint32_t m_backoffCount

Counter for current backoff remaining.

Time m_backoffStartTime

The backoff start time.

TracedValue<uint32_t> m_currentBackoffSlots

The last value drawn for backoff.

Time m_deferTime

The defer time of LBT algorithm.

double m_edThreshold

ED threshold to be used for energy detection.

bool m_grantRequested

The indicator for tracking whether the channel access grant is requested.

Time m_lastBusyTime

The last time at which the channel was busy.

Time m_lastTxopStartTime

The last grant start time.

Time m_mcot

The maximum channel occupancy time.

Ptr<UniformRandomVariable> m_rng

The uniform random variable used to choose random value for the backoff counter.

Time m_slotTime

The duration of a single slot when listening the channel, that is considered by LBT algorithm.

LbtState m_state

LBT algorithm state.

EventId m_waitForBackoffEventId

The ID of the event that is triggered once that the backoff is over.

EventId m_waitForBusyEventId

The ID of the event that is triggered once that the channel busy state is over.

EventId m_waitForDeferEventId

The ID of event that is triggered when defer time is over.

Function documentation