Radio frequency tag and reader with asymmetric communication bandwidth

Abstract

A method and apparatus to overcome fundamental shortcomings in narrow band as well as wide band RFID solutions through offering a hybrid solution that utilizes benefits of narrow band in the downlink direction with the benefits of ultra wide band in the uplink. The invention encompasses a multitude of methods, including an approach to increase the ability to capture electromagnetic energy from the reader.

1 . A system with a multitude of radio transceivers called readers and a multitude of radio transceivers called tags, wherein the readers transmit radio frequency signals to the said tags in a narrow frequency band and receive radio frequency signals from the said tags in an ultra wide frequency band. Conversely, the said tags transmit in narrow band and receive in ultra wide band.  
   
   
       2 . A system as in  1  where each individual tag maintains the capability to store, erase, update and process local and incoming data.  
   
   
       3 . A system as in  1  and  2 , where the signal energy transmitted from the reader in narrow band also electrically and remotely energizes the circuitry in the tags individually or collectively over the air to wholly or partially substitute battery or other sources of power in the tag.  
   
   
       4 . A system as in  1  to  3 , where the relationship between tag and reader is reversed, i.e. the tag transmits in narrow band and receives in ultra wide band, while the reader transmits in ultra wide band and receives in narrow band.  
   
   
       5 . A system as in  1  to  4  whereas the network of the multitude of tags and readers can be organized and supervised by a multitude of central or distributed servers that can control, process and store the information flowing in the network of tags and readers.  
   
   
       6 . A system such as in  1  to  5  where readers and tags are both capable of using ultra wide band radio for both transmission and reception of data, while the tags are still powered by narrowband signals from the readers.  
   
   
       7 . A system as in  1  to  6  where individual tags and readers can listen to other propagating units, including other tags and readers in order to organize their activity in the total network.  
   
   
       8 . An RFID system that utilizes several circuits each tuned for different frequencies in the receiving front-end so as to enable the tag to simultaneously capture electromagnetic energy in the said frequencies.  
   
   
       9 . A system such as in  1 - 8  where the narrowband receivers and the narrowband transmitters are completed with such functionality to enable them to be compatible with legacy narrowband methods and devices.