Why would a wireless smart card antenna have one larger loop and three smaller loops instead of four similar size loops?
A new antenna technology for dual interface smartcards makes it possible to integrate
an antenna into the card body that does not need wired contacts to the chip module (cf. [3, 7, 8]). Instead, the antenna in the card body has a few additional turns around the area where the chip module is embedded (see Fig. 16(c)). This card body antenna inductively couples into a tiny loop antenna that is directly integrated into the chip module (see Fig. 16(b)). This simplifies the card production process as the antenna does not need to be attached (e.g. glued, welded or soldered) to the chip module.

Not much help, but the CA and EA initials may hold meaning...

Evaluation of Contactless Smartcard Antennas (2015)


Fig. 2 represents the layout of the smart card with the free space available for UHF tag. M1 is depicting the [blue] available space for RFID UHF tag, while M2 is showing the NFC track tracks around the bank card, M3 and M4 are showing the area occupied by the EMV chip and the card embossment the red lines are showing the NFC tag tracks around the bank card, yellow lines are depicting the free available space for RFID UHF tag while, the green coloured hatched area is showing the area occupied by the EMV chip and card embossment. As the UHF tag antenna geometry is dipole so for symmetrical design the rectangular blue hatched area is allocated for UHF tag design with area...

Still unclear to me, but it may be something to do with embossment area.

A Novel Design of UHF RFID Passive Tag Antenna Targeting Smart Cards Limited Area (2018)

Introductory reading:
https://wikipedia.org/wiki/Contactless_smart_card#Technology