Omnidirectional RFID UHF antennas with medium (~25mm) range recommendations?

Question

Please bear with me as I couldn't even be considered a novice yet. I'm just a coder with an idea that I want to try out using RFID technology. 
 I want to identify and record data from passive RFID tags that are up to approximately 10 inches (25 cm) away from the device in any direction. There may be a few inches of low density foam between the antenna and the RFID tags. Small size and weight are important factors. Number of simultaneous tag reads... let's say, up to 5 at a time. 
 Based on my online research, I've come to the conclusion that a UHF reader is the way to go however, it seems like all antennas are either very short (few inches) or very long range. Can anyone recommend some antennas that might be suitable for these requirements? 
 Thanks in advance.

shabaz · Answer

Board with the 868 MHz ceramic patch antenna attached. 
 
 The underside has the U.FL connector, and should have a 0-ohm resistor, but I've not soldered that in yet (because I want to measure the impedance first). 
 
 I used a U.FL to SMA socket cable (pre-assembled). 
 For 3D-printing an enclosure, the main dimensions are the same as Hammond 1551XBK, but the depth will need to be tailored to suit whatever connector is used, if it is a panel-mount item.

shabaz · Answer

Measurements! 
 The results are not significantly different from the datasheet, for almost 2/3 of the frequency span. I wouldn't expect it to be identical anyway since there's no guarantee I tested in the same environment or the same orientation. I happened to test with the antenna facing vertically upwards. 
 This was my first time using the NanoVNA (there are different models, I have the -H4 model) to measure an antenna. Impressive how good it is. Now I understand why people rave about NanoVNAs, it's justified.

Omnidirectional RFID UHF antennas with medium (~25mm) range recommendations?

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