IWR6843AOP: IWR6843ARQGALPR and PMIC : LP87524JRNFRQ1

KARTHIKEYAN SUNDARAM

Part Number: IWR6843AOP
Other Parts Discussed in Thread: , UNIFLASH

Tool/software:

We are planning to develop a people presence and distance detection system within a defined zone of approximately 2 x 2 meters, using the IWR6843AOP mmWave Radar (MPN: IWR6843ARQGALPR). The radar will operate in standalone mode and communicate with a Raspberry Pi Compute Module 5 via UART.

For power management, I plan to use the LP87524JRNFRQ1 PMIC as per the reference design.

I have several questions regarding the hardware integration and firmware development:

1. Use of Mission AOP Board Without Breakaway Board

I noticed that the IWR6843AOPEVM consists of two sections: the Mission AOP Board and a Breakaway Board. Based on my understanding, the Mission AOP Board can function independently without the Breakaway Board.
Could you please confirm this?

2. Firmware Upload in Custom Board Design

We are designing our own board similar to the Mission AOP Board, which includes the mmWave sensor, PMIC, QSPI Flash, USB-to-UART, and crystals.

How can we upload the firmware in this custom design?
Since the PMIC requires control via I2C by the IWR6843AOP, how can the sensor initiate this sequence without having firmware preloaded?

3. Flashing the QSPI NOR Memory

Is it necessary to pre-flash the QSPI NOR memory before soldering it onto the PCB, so that the IWR6843AOP can boot from it successfully?

4. PMIC and Bootloader Support

Alternatively, does the IWR6843AOP have any pre-programmed bootloader or firmware to configure the PMIC for initial boot and enable UART functionality for firmware upload using tools like UniFlash?

5. Communication Interface Recommendation (UART vs SPI)

Which interface is recommended between UART and SPI for data communication between the IWR6843AOP and Raspberry Pi CM5, considering performance and stability?

6. Deployment in Metal-Rich Environment (Clean Room)

The sensor will be deployed in an OHT clean room environment, where metallic structures are likely to surround the sensor within 1 meter.

Will the sensor be able to accurately detect people presence and distance in such an environment?
Are there any configuration or shielding recommendations to improve performance in metal-heavy surroundings?

7. Sensor Protection Design

We plan to enclose the sensor in a plastic box and are considering placing a glass panel with a 2–3 mm air gap directly above the radar module (Above AOP Antenna).

Would this affect the radar performance?
Are there recommended materials or design guidelines for covering and protecting the sensor without interfering with its detection capabilities?

I would appreciate your expert guidance on the above points to ensure a successful integration and deployment of the IWR6843AOP radar module.

Thank you for your support.

3 months ago

+1 Josh Dye 3 months ago

TI__Mastermind 20611 points

Hello,

KARTHIKEYAN SUNDARAM said:
Based on my understanding, the Mission AOP Board can function independently without the Breakaway Board.

This is correct; however it is important to note that if you separate the mission board section you will no longer be able to connect the IWR6843AOP device with the DCA1000 for raw ADC data capture nor will you be able to connect the board to the MMWAVE ICBOOST for debugging in CCS. However, flashing and functional mode operation should work as expected.

2, 3, 4.

KARTHIKEYAN SUNDARAM said:
Is it necessary to pre-flash the QSPI NOR memory before soldering it onto the PCB, so that the IWR6843AOP can boot from it successfully?

This is not required. One might optionally choose to do this in production to save time on programming the flash but it's definitely not required since the bootloader will read the image over a serial connection and write it to flash memory if the device is set to flashing mode.

KARTHIKEYAN SUNDARAM said:
Alternatively, does the IWR6843AOP have any pre-programmed bootloader or firmware to configure the PMIC for initial boot and enable UART functionality for firmware upload using tools like UniFlash?

Yes, this understanding is correct. 6843 bootloader flow documentation can be found here.

KARTHIKEYAN SUNDARAM said:
Will the sensor be able to accurately detect people presence and distance in such an environment?

If there is a lot of meatal nearby, especially within the field of view of the radar, you will likely see 'ghost detections' as the effect of multipath reflections caused by the nearby metal objects. This can affect the accuracy of presence detection/people tracking algorithms. Multipath reflection is a challenge and we do not have a general solution to eliminate multi-path; however, we have noticed that multipath reflection changes faster and is in general weaker. Some methods can be considered to help reduce ghost reflection. For example, the Capon based people tracking demo chain detects less ghosts than range-Doppler chain, you can also play with the CFAR threshold. Or build in more intelligence on the higher level module, for example, If you know the room size, you can also filter some ghost detections.

KARTHIKEYAN SUNDARAM said:
Would this affect the radar performance?

It might have some small effect on performance depending on the thickness of the glass. We have done this setup for an experiment, refer to the results on this page.

KARTHIKEYAN SUNDARAM said:
Are there recommended materials or design guidelines for covering and protecting the sensor without interfering with its detection capabilities?

Yes. Please refer to the mmWave Radar Radome Design Guide.

Best regards,

Josh

0 KARTHIKEYAN SUNDARAM 3 months ago in reply to Josh Dye

Prodigy 10 points

Hi Josh Dye,

Thank you for your detailed explanation. I’ll review the documents you mentioned and begin working on the design.

I’ll reach out to you if I encounter any issues or need further clarification.

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