Glossary

SPARK SDK

The piece of software used to develop an application based on SPARK Microsystems UWB wireless technology. It includes various components such as application examples, board support packages, drivers and libraries.

SR1000 Series

The SPARK Microsystems SR1000 Series includes all SR1XXX transceivers currently available.

Audio Core Glossary

ADPCM

Adaptive Differential Pulse-Code Modulation is an audio compression algorithm that can achieve a compression factor of 4 (i.e., 16-bit samples become 4-bit samples). See the Audio Compression section for more details.

Aliasing

Distortion caused by high frequency content (higher than the Nyquist frequency) folding back into the original signal. This is usually solved by proper low-pass filtering before sampling.

Audio API

The Audio Core’s set of public functions meant to be called by an audio application. See the Audio Core API section for more details.

Audio Consumer

An endpoint used to consume audio samples (consumer) in an audio pipeline. See the Audio Endpoint section for more details.

Audio Core

SPARK Microsystems’ audio library. See the Audio Core section for more details.

Audio Device

A physical device that makes use of the SPARK Microsystems Audio Core.

Audio Endpoint

Occupies both ends of an audio pipeline. It can produce and/or consume audio samples. It implements an endpoint interface. Common examples are a hardware audio codec and the SPARK Wireless Core. See the Audio Endpoint section for more details.

Audio Header

The part of the audio packet that contains audio protocol information. See the Audio Header section for more details.

Audio Packet

The combination of the audio header and the audio payload.

Audio Payload

The part of the audio packet that contains audio samples.

Audio Pipeline

The path the audio samples will go through from one endpoint to another. An audio pipeline is a concept that is local to an audio device. See the Audio Pipeline section for more details.

Audio Processing

Operations applied on audio samples to modify them. Examples are compression/decompression and sampling rate conversion. See the Audio Processing Stage section for more details.

Audio Producer

An endpoint used to produce audio samples (producer) in an audio pipeline. See the Audio Endpoint section for more details.

Audio Stream

A general term to talk about the data the audio represents. For example, a microphone audio stream or the audio stream from an audio streaming service.

CDC

Clock Drift Compensation is a sort of audio processing that compensates the difference between the audio clocks of two audio devices using resampling for gradually creating and dropping samples. See the Clock Drift Compensation section for more details.

Decimation

The process of reducing the sampling rate by first low-pass filtering then throwing away samples.

Downsampling

The process of reducing the sampling rate without low-pass filtering. Can be loosely used as a synonym of decimation.

Interpolation

The process of increasing the sampling rate by first adding zero-valued samples between the original samples then low-pass filtering.

SAC

SPARK Audio Core.

SRC

Sampling Rate Conversion is a sort of audio processing that increases or decreases the sampling rate of already sampled audio samples through interpolation and decimation respectively. See the Sampling Rate Converter section for more details.

Upsampling

The process of increasing the sampling rate without low-pass filtering. Can be loosely used as a synonym of interpolation.

Wireless Core Glossary

ARQ

Automatic repeat request is an error-control method that uses acknowledges and retransmissions.

Auto-Reply

Auto-Reply is a mechanism which allows the transceiver to automatically send a frame with minimal delay after a reception. Not to be confused with Auto-Reply Timeslots which make use of the auto-reply mechanism to send a payload.

Beacon

A Beacon is a transmitted (generally broadcasted) frame for the sole purpose of synchronization between devices of a TDMA network. See the Sync Timeslot (Beacon) section for more details.

CCA

Clear Channel Assessment is a mechanism for determining whether the medium is idle or not. See the Clear Channel Assessment (CCA) section for more details.

Channel

A Channel regroups a set of parameters required to configure a transmission such as frequency, pulses and pre-amplifier gain. See the Channel section for more details.

Concurrency

Concurrency is a generic term that abstracts all the mechanisms required to enable the operation of multiple independent networks concurrently. See the Concurrency section for more details.

Connection

A Connection defines a unidirectional communication link between two devices. See the Connection section for more details.

Coordinator

This is the role of the device on which all other devices synchronize. The Coordinator will generally be the device sending the Beacon.

Dual Radio

This is a special mode of operation allowing a device to use two transceivers for reception instead of one. This is generally used to extend RF coverage. See the Dual Radio section for more details.

FDMA

Frequency-Division Multiple Access is possible to achieve by ensuring that simultaneous transmissions use non-overlapping frequencies.

FEC

Forward Error Correction is directly supported by the transceiver and increases robustness of transmissions at the cost of frame size inflation. See the Forward Error Correction (FEC) Level section for more details.

Frame

A Frame represents the complete bitstream sent over-the-air by the transceiver. See the Frame Structure section for details.

Modulation

The transceiver supports various Modulation strategies which defines how to shape the RF energy to represent bits. See the Modulation section for more details.

Network

A Network defines a group of intercommunicating devices. In a TDMA network, those devices will know each other in advance and share the same schedule.

Node

A Node corresponds to any device part of a SPARK wireless network. A Node can also take on the role of the Coordinator on which all other nodes of the network will synchronize.

Preamble

The Preamble is an energy pattern all frames start with. The receiver will use this energy pattern to adjust its reception gain in preparation of the following frame reception. See the Frame Structure section for more details.

Pulse

Pulses are energy bursts that compose a symbol. More pulses or wider pulses means more energy.

ReTX

The Retransmissions are transmissions of frames which contains an already sent payload, but was not ACKed. Retransmissions are essential to maximize the robustness of an RF link between 2 devices. See the Retransmission Margin section for more details.

ReTX Margin

The Retransmission Margin is the portion of the wireless link throughput that is free to use for retransmissions. For more details, see the Retransmission Margin section.

Schedule

Implicitly referring to a TDMA Schedule, this defines the timeslots in which devices can transmit or receive. See the Schedule section for more details.

SWC

SPARK Wireless Core.

Symbol

A Symbol refers to the pulse pattern which represents a bit over-the-air.

Synchronization

Synchronization refers to the Nodes adjusting their timing to match the Coordinator’s own. See the Synchronization Methods section for more details.

Syncword

Following the preamble, the syncword is a bit pattern that allows the receiver to synchronize on the incoming frame data. See the Frame Structure section for more details.

TDMA

Time-Division Multiple Access is a method by which time is divided into pre-determined periods (also called timeslots) allocated for specific transmissions. See the Time Division Multiple Access section for more details.

Throttling

This mechanism allows the user to reduce the wireless link throughput on-the-fly by disabling certain timeslots. Useful for power management. See the Link Throttling section for more details.

Timeslot

A Timeslot is a short period of time dedicated for a specific transmission. Timeslots compose a schedule. See the Time Division Multiple Access section for more details.

TTL

Time-to-Live is a mechanism allowing the user to define a maximum retransmission time or a maximum retransmission count. Past any of these limits, frames will be dropped by the transmitter.

Wireless Core

The Wireless Core is a software module which enables users to create a wireless link by using its API. See the Wireless Core section for more details.

Wireless Core API

This is the main public API that the user can use to create applications with the SR1000 Series transceivers. See the Wireless Core API section for more details.

Ranging Core Glossary

Distance Calibration

Compensating for the fixed delay overhead of the measured round-trip time. See the Distance Calibration section for more details.

Initiator

This is the role of the device which initiates the data exchange for ToF measurements. See the Roles section for more details.

Initiator’s Receiver Wait Time

This is the time a receiver has been actively waiting before a receiving frame is detected. Precisely, it represents The amount of time spent in symbol clock periods waiting in reception for information to decode before detecting the last received frame’s synchronization word.

Preamble Phase Correlation Metrics

Preamble phase correlation metrics are made available by the transceiver upon reception of a packet. See the Preamble Phase Correlation Metrics section for more details.

Responder

This is the role of the device which answers the request from the Initiator. See the Roles section for more details.

SRAC

SPARK Ranging Core.

ToF

Time-of-Flight is a standard method used to get the distance between two transceivers based on signal travel time. See the Distance Calculation section for more details.