IEEE standard – 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 efficient and reliable.

Herein, the App-based OCC PHY configuration mechanism shall include

1. The general description of the PHY-reconfiguration method
2. The device architecture
3. Specification of PHY PIB attributes within IEEE 802.15.7m standard for OCC

Note that: The App-based configuration has been already approved by IEEE 802.15.7m TG committee.

This post explains the configuration based on IEEE 802.15.7m draft D4 standard.

Why we need App-based configuration for OCC PHY?

There are many modulation schemes available for OCC. A particular Rx must know which modulation is used at Tx for the demodulation.

Thus, the configuration of PHY for Tx being recognizable by Rx is indispensable. Especially, when the PHY frame does not contain PHY header due to the forbidden of overhead in OCC modes. The configuration of modulation schemes is software-based, or app-based, called App-based PHY configuration.

General Description

It has been known that the configuration of the physical layer data unit (PPDU) frame format is typically done via the transmission of PHY header subfield within the PPDU. Such that over-the-air configuration seems to be intolerant for OCC modes operating at data rates as low as 10kbps or much lower rate. Indeed, the current OCC PHY modes in the IEEE 802.15.7m (TG7m) draft standard operating at the bit rate ranging from tens-of-bps to Mbps. As a consequence, the TG7m committee has discussed and introduced a brand-new configuration of PHY modes without the need of PHY headers.

The PPDU configuration, such as frame size modulation and coding choice, and optical clock rate, etc., shall be performed via PHY-layer personal area network information-based (PIB) attributes. In the other word, the arrangement of configurable PPDU related parameters is APP-based; in an example, when a smartphone user downloads the app, it has to accompany PIB-values to let the camera know how to demodulate the light waveform. This paradigm has been approved by the TG7m committee, and the following screen modulations are adhered to accordingly.

The overall architecture for VPAN is illustrated as in Figure 2.

The discussion issue is about the configuration manner of an operating mode among multiple given modes, particularly PPDU frame format without the over-the-air transmission of PHY headers. This means the App-based device should be able to know the proper PPDU format for its decoding. Imagine when the user downloads the software app at a shopping mall, it contains all the necessary information including the type of PPDU format used at the shopping mall. Accordingly, the information for the communication mode can pass to the PHY/MAC layer (particularly to PHY/MAC PIB for the configuration) via the device management entity (DME).

The PHY-layer personal area network information-based (PHY PIB) attributes are within the physical-layer management entity (PLME), see Figure 101. The manner to use (GET and SET values) PHY-PIB-attributes is described in section 9.2. PHY Management service of the IEEE 802.15.7-2011.

New PHY PIB Attributes for OCC

The PHY or MAC PIB comprises the attributes required to manage the PHY or the MAC of a device. Each of these PHY PIB attributes can be read using the PLME-GET.request, or written using PLME-SET.request primitives, respectively.

Necessary PHY PIBs for the configuration of PPDU formats for each PHY operating modes with suggested values are introduced as follows.

Table 1 – Overall PHY PIB attributes (Part of IEEE 802.18.7m)

Table 2 – OCC PHY modes identification (Part of IEEE 802.18.7m)

//The Bold text in Table 2 indicate that I can provide you the open source implementation for your evaluation. I will invite some colleagues for helping me publishing more open source in a near future.

Table 3 – PHY PIB attributes for S2-PSK mode (Part of IEEE 802.18.7m)

Table 4 – PHY PIB attributes for HS-PSK mode (Part of IEEE 802.18.7m)

Table 5 – PHY PIB attributes for A-QL mode (Part of IEEE 802.18.7m)

Table 6 – PHY PIB attributes for HA-QL mode (Part of IEEE 802.18.7m)

Table 7- PHY PIB attributes for RS-OFDM mode (Not part of IEEE 802.18.7m)