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Five reasons to promote OCC

The light spectrum is a rescue solution for the exponential growth of wireless connectivity demand. The bandwidth of light is 1000 times larger than the entire RF bandwidth. Among light communication technologies, Optical Camera Communication (OCC) is an entirely software-based solution, which is the best compatible with existing infrastructures such as commercial cameras and lighting. … Continue reading Five reasons to promote OCC

Optical camera communication (OCC) with Matlab code

NOTE: This C-OOK Matlab package is independent from other C-OOK packages. Please email us for video demonstration and further technical details. In this code package, we demonstrate a system utilizing a LED and Camera (rolling shutter mechanism). Fig. 1. System Block diagram of C-OOK Matlab Package Transmitter In the transmitter side, we use a PC … Continue reading Optical camera communication (OCC) with Matlab code

NEW 2D-OFDM Codes available

We now release new 2D-OFDM Codes (2D ACO-OFDM) and update existing Code adding many interesting features. Notably, TWO MORE new software packages are now included. NEW Package 1 (ACO/DCO-OFDM Simulation) New features This allows for choosing different modulation modes, including Modulation option: 2D ACO-OFDM or 2D DCO-OFDMChangeable clipping factor for reducing PAPREnable Inner-FEC and spatial-pilots … Continue reading NEW 2D-OFDM Codes available

A-QL Code Update available

We now release an update of the A-QL Code by adding several interesting features: Switching between 16*16 and 32*32 cells modesAuto-threshold feature for RXEnable button for option of RGB colors calibrationFeedback nodes for a clean block diagram Please download the following PPT file for a review of the software User Interface (TX and RX). A-QL … Continue reading A-QL Code Update available

Implementation of HA-QL Code

HA-QL (Hidden Asynchronous Quick-Link) is a hidden modulation mode among Screen-2-Camera operating modes within the IEEE 802.15.7-2018 Optical Wireless Communication standard. An interesting feature of HA-QL is that it allows for controlling the peak-to-peak amplitude of the intensity modulation, from a visible code to a hidden code. The HA-QL Code Project is cleaned, well-packed and documented. Technical … Continue reading Implementation of HA-QL Code

(PPT) Presentation of technical features: A-QL vs 2D-OFDM

The following PPT file presents the technical features of A-QL code versus 2D-OFDM code. Also, we have included the performance comparison between the codes. Please download the file for more technical details. Presentation of technical features in 2D-OFDM and A-QL (PPT file)Download Notice: A-QL stands for Asynchronous Quick Link, a two-dimensional multi-band color code sequential transmission protocol from … Continue reading (PPT) Presentation of technical features: A-QL vs 2D-OFDM

Performance of Screen OCC: 2D-OFDM vs. A-QL

In the previous posts, the implementation demo and the implementation guidance of the Screen-OFDM system were shown. The measured performance comparison between Screen-OFDM and a traditional A-QL in IEEE 802.15.7m is reported in this post. Overview of 2D-OFDM vs A-QL A-QL is the single-carrier modulation while 2D-OFDM is the multi-carrier modulation approach applied for the … Continue reading Performance of Screen OCC: 2D-OFDM vs. A-QL

Customizing MAC for OCC Modes

This post discusses the topic related to OCC MAC and MPDU.   IEEE 802.15.7m OCC MAC Layer "Use of over-the-air MAC frame configuration is forbidden for PHY types IV, V and VI. It is mandatory MAC frame configuration be done via the MAC PIB. This is due to the fact that unlike traditional wireless LAN/PAN, the data … Continue reading Customizing MAC for OCC Modes

Software-defined Configuration method for OCC Systems

The purpose of the post is to specify the PIB attributes for configuring a particular OCC PHY mode. Any OCC PHY mode is co-existing with the others and recognizable by a specific receiver once the PIBs are specified. The configuration of PHY-PIB attributes is software-defined (App-based). Without using PHY-frame overhead, the App-based configuration is communication … Continue reading Software-defined Configuration method for OCC Systems

PPDU: PHY frame format for S2-PSK & HS-PSK

This post reviews the design of the Physical-layer Packet Data Unit (PPDU) for S2-PSK and HS-PSK operating modes within PHY IV of IEEE 802.15.7m. The general structure of PPDU for all OCC Operating modes is illustrated in Figure 1. SHR: Synchronization Header PHR: Physical-Layer Header HCS: Header Check Sequence PSDU: PHY service data unit "Use of over-the-air PHY … Continue reading PPDU: PHY frame format for S2-PSK & HS-PSK

HS-PSK: High-rate transfer over RoI(s)

HS-PSK is an operating mode being standardized at IEEE 802.15.7m. This post describes what it is for and how it operates. Figure 1 illustrates an example in which an Rx can select the link properly for an intended usage. The link setup procedure is solved by the RoI-Signaling waveform, while this high-rate waveform is additionally … Continue reading HS-PSK: High-rate transfer over RoI(s)

S2-PSK: A choice for RoI-Signaling

S2-PSK is an operating mode being standardized at IEEE 802.15.7m. This post describes what it is for and how it operates.   Technical Considerations for a RoI-signaling Waveform Even though RoI-signaling mode has a very low data rate, it is indispensable to the OCC system operating in a challenging condition such as V2X. The general … Continue reading S2-PSK: A choice for RoI-Signaling

PPDU: PHY frame format for CM-FSK & C-OOK

This post reviews the design of the Physical-layer Packet Data Unit (PPDU) for CM-FSK  and C-OOK operating modes within PHY V of IEEE 802.15.7m. For a detailed explanation of how these modes operate, please visit the previous CM-FSM post and the previous C-OOK post. The comparison between these modulation schemes for rolling shutter OCC was discussed … Continue reading PPDU: PHY frame format for CM-FSK & C-OOK

PPDU: PHY frame format for Screen Modulation Systems (A-QL & HA-QL)

This post reviews the design of the Physical-layer Packet Data Unit (PPDU) for A-QL and HA-QL operating modes within PHY IV Screen modulation of IEEE 802.15.7m. For implementation, the Data Frame Format is crucial; each operating mode has its packet format and the format specification has its reason. At least, time is spent on optimizing … Continue reading PPDU: PHY frame format for Screen Modulation Systems (A-QL & HA-QL)

HA-QL: Part 2 – Hiding data into Screen using Wavelet Transform

HA-QL (Hidden Asynchronous Quick-Link) is a hidden modulation mode among Screen-2-Camera operating modes those are being standardized at IEEE 802.15.7m. The previous post explains the principle to generate a hidden code on the screen using an additional intensity modulator after the bit-intensity mapper. However, the modulation of screen intensity dramatically degrades the communication performance. In … Continue reading HA-QL: Part 2 – Hiding data into Screen using Wavelet Transform

HA-QL: Part 1- Intensity modulation for Hidden Screen Code

HA-QL (Hidden Asynchronous Quick-Link) is a hidden modulation mode among Screen-2-Camera operating modes those are being standardized at IEEE 802.15.7m. This post describes what it is for and how it operates. Introduction The name Hidden A-QL briefly describes how it operates. The mapping from bits into the screen cells during modulation in HA-QL shall follow … Continue reading HA-QL: Part 1- Intensity modulation for Hidden Screen Code

A-QL: Part 2 -BER Measurement

A-QL (Asynchronous Quick-Link) is a Screen-2-Camera operating mode being standardized at the IEEE 802.15.7m. This post introduces the BER measurement method and the performance of A-QL system. See this video demo for the BER measurement scenario: https://www.youtube.com/watch?v=Mkq2lYKzQsQ   Experimental Setup The scenario for measuring BER is illustrated in Figure 1. The bit rate is measured … Continue reading A-QL: Part 2 -BER Measurement

A-QL: Part 1- Introduction of Reliable Screen-Camera Communication

A-QL (Asynchronous Quick-Link) is a Screen-2-Camera operating mode being standardized at IEEE 802.15.7m. This post describes what it is for and how it operates. Figure 1 - Example of color code displaying with video on a screen And before we start talking about A-QL system, a short demo of it is here: https://www.youtube.com/watch?v=B6uBTSdh44Y Introduction The … Continue reading A-QL: Part 1- Introduction of Reliable Screen-Camera Communication

Rolling shutter OCC: Communication distance vs Data rate Trade-off

The classification of OCC technologies has been given. Being a part of non-flicker modulation series, with the vast usage of rolling shutter cameras in the camera market, the use of rolling shutter cameras in OCC systems takes advantage of the high sampling rate of the rolling shutter mechanism, which sequentially exposes pixel lines to the … Continue reading Rolling shutter OCC: Communication distance vs Data rate Trade-off

C-OOK: Customizing OOK for Optical Camera Communication

C-OOK stands for Camera ON-OFF Keying, is also an operating mode being standardized in IEEE 802.15.7m. This post reviews the operation of this mode and highlights its characteristics. See video demo 1 (Manchester coded for Rolling shutter OCC): https://www.youtube.com/watch?v=tMaR7B5M3QI See video demo 2 (4B6B coded for Rolling shutter OCC): https://www.youtube.com/watch?v=wPbeZZxEMVY C-OOK for OCC and its … Continue reading C-OOK: Customizing OOK for Optical Camera Communication

CM-FSK: Customizing FSK for Optical Camera Communication

CM-FSK stands for Camera M-ary Frequency Shift Keying, is also an operating mode being standardized in IEEE 802.15.7m. This post reviews the operation of this mode and highlights its characteristics. See video demo 1 to have a brief understanding of CM-FSK System: (7m transmission) https://www.youtube.com/watch?v=cUt5zbRSyoQ Also, video demo 2 (35m transmission distance): https://www.youtube.com/watch?v=BVqh570bCRY&t=5s   FSK … Continue reading CM-FSK: Customizing FSK for Optical Camera Communication

FEC: Generation of Reed-Solomon and Convolutional Code

Reed Solomon and Convolutional Code are chosen for IEEE 802.15.7-2011 and IEEE 802.15.7m implementation. In this post, we will review the generation of the codes and simulate their performance for comparison. Reed Solomon  Systematic RS codes are used for FEC (typically outer FEC) with GF(16), generated by the polynomial x4+x+1. The generators for the RS(n, … Continue reading FEC: Generation of Reed-Solomon and Convolutional Code

What is Optical Region-of-Interest Signaling?

In the context of a safety assistance communication-based solution, OWC is a strong candidate for delivering the V2V communication power to cars. It is realized that the LED lighting is quipped to car mandatorily, meanwhile, a camera is considered as one of the indispensable sensors for car vision. The existence of supportive infrastructure enables the … Continue reading What is Optical Region-of-Interest Signaling?

A comparison between OCC standardization groups within IEEE 802.15

This post briefly reviews the current status of standardization groups within IEEE 802.15 There are IEEE standards covering the optical spectrum, IEEE 802.15.7-2011 std., known as VLCIEEE 802.15.7m std., (publication in 2018, as expected), including OCC modesIEEE 802.15.13 std., (ongoing), adding LiFi (IEEE 802.15.7-2011 std. is also the base document as IEEE 802.15.7m)IEEE 802.11, introducing LiFi to 802.11IEEE 802.15 … Continue reading A comparison between OCC standardization groups within IEEE 802.15

PHY modes within IEEE 802.15.7m draft – a quick review

PHY operating modes  The latest IEEE 802.15.7m draft standard (until Aug. 2018) is on the Sponsor Balloting recirculation. This version has updated a lot in compared to the previous version before LiFi modes are moved to new task group under IEEE 802.15. A list of operating modes between two drafts is a good start. Notation … Continue reading PHY modes within IEEE 802.15.7m draft – a quick review

OCC Standardization Roadmap

OWC Standards under IEEE 802 There are IEEE standards covering the optical spectrum, IEEE 802.15.7-2011 std., known as VLC IEEE 802.15.7m std., (publication in 2018, as expected), including OCC modes IEEE 802.15.13 std., (ongoing), adding LiFi (IEEE 802.15.7-2011 std. is also the base document as IEEE 802.15.7m) IEEE 802.11, introducing LiFi to 802.11 IEEE 802.15 … Continue reading OCC Standardization Roadmap

OCC Use Cases/ Promising Services

Figure 1 - Examples of promising use cases using OCC Various application fields of OCC include Indoor lighting Digital Signage Traffic lighting, V2V, V2X Interactive Display with Screen Augmented Reality experience with Smartphones There are plenty of promising applications with OCC. I have drawn several illustrations to explain "where OCC can be used" and "how … Continue reading OCC Use Cases/ Promising Services

Classification of OCC Technologies

Table 1- Classification of OCC, its expected performance, and intended usages Given that various modulation schemes for OCC systems have been investigated till the date, the proper modulation scheme should depend on both Tx and Rx. Table 1 suggests to classify OCC schemes into four categories under the following considerations: (i) The method by which … Continue reading Classification of OCC Technologies

What is Optical Camera Communication?

Figure 1- Example of  OCC promising services (a) OCC vehicular use case. (b) OCC indoor use case OCC: Optical Camera Communication VLC: Visible Light Communication LiFi: Light Fidelity OWC: Optical Wireless Communication What is Optical Camera Communication? OCC aims to deliver data from the light source(s) to the camera. Artificial lights (LED light) are available everywhere human being … Continue reading What is Optical Camera Communication?