Is it possible to have a 1cm x 1cm UHF RFID tag that can be read from one meter?

Yes, it is technically possible to have a 1cm x 1cm UHF (Ultra High Frequency) RFID tag that can be read from one meter away. 

For example:

Size Dia1cm size PCBD10 reading reading range up to 1.5 meter

Size 1cmx0.4cm pcb1004 reading reading range up to 1.35 meter

Size 0.6cmx0.6cm pcb0606 reading reading range up to 1.1 meter

the more UHF RFID Tag procucts view http://www.oppiot.com/pcb-on-metal-rfid-tags.html

However, several factors need to be considered to achieve this:

1.Antenna Design: The design of the antenna plays a crucial role in determining the read range of an RFID tag. For a tag as small as 1cm x 1cm, the antenna design needs to be carefully optimized to maximize its performance.

2.RFID Chip: The RFID chip used in the tag should be selected based on its sensitivity and power requirements. It should be capable of operating at UHF frequencies and be compatible with the desired read range.

3.RFID Reader: The RFID reader also plays a significant role in determining the read range. It should be capable of providing enough power to energize the tag and receive its response signal.

4.Operating Environment: The environment in which the RFID system operates can affect the read range. Factors such as interference, metal objects, and other RF signals can impact the performance of the RFID system.

5.Regulatory Considerations: Depending on the region, there may be regulatory limitations on the power levels allowed for RFID systems operating at UHF frequencies. Compliance with these regulations is essential.

By carefully selecting components, optimizing the design, and considering the operating environment, it is possible to develop a small UHF RFID tag with a read range of one meter or more. However, achieving this requires careful engineering and testing to ensure reliable performance.