Baseband

Service

BASEBAND – Baseband service

Agents offering the Baseband service are most commonly modem drivers (or simulators). They support a set of messages and parameters that are explained below. Baseband service providers may optionally support optional capabilities for timed transmissions or recordings.

Capability Description
TIMED_BBTX Transmissions of signal at specified time
TIMED_BBREC Recording of signal at specified time

A preamble is usually added to a transmitted baseband signal, so that the receiving modem can identify the incoming signal. The receiving modem captures the signal when it detects the preamble, and then sends a RxBasebandSignalNtf. If a modem supports multiple preambles, the TxBasebandSignalReq can specify the preamble to be used. Setting the preamble to 0 results in a signal transmission without a preamble. Such a transmission will ordinarily not be received by any modem, unless it is recorded by an explicit RecordBasebandSignalReq at the appropriate time.

Implementations

Requests and Responses

Request Possible Responses Description
TxBasebandSignalReq AGREE, REFUSE, FAILURE Transmit a frame with a baseband signal
RecordBasebandSignalReq AGREE, REFUSE, FAILURE Record a baseband signal
ParameterReq ParameterRsp Get/set/list parameters
CapabilityReq CONFIRM, DISCONFIRM, CapabilityListRsp Check/list capabilities

Notifications

Notification Topic Description
RxBasebandSignalNtf default Frame with baseband signal recevied/recorded
ParamChangeNtf PARAMCHANGE Notification about the modified parameter

Parameters

Parameter r/w Description
carrierFrequency rw Default carrier frequency for baseband signals (Hz)
basebandRate rw Default sampling rate for baseband signals (Hz)
preambleDuration ro Preamble duration (s)
maxSignalLength ro Maximum baseband signal length (in samples) for transmission/reception/recording
maxPreambleID ro Maximum preamble identifier supported by the agent
signalPowerLevel rw Signal transmission power level in dB