A bolus (100) that communicates with an external transceiver (106) by way of radio waves (104) produced by an electrically small H-antenna (221) is described. The electrically small H-antenna (221) is connected to a conductive cylindrical antenna (223) that houses a battery and chipset that includes a transceiver (106), identification information and at least one sensor. The H-antenna (221) and the conductive cylindrical antenna (223) are arranged so that electrical currents that produce the radio waves (104) are essentially always aligned to work together. The bolus (100) is essentially a hermetically sealed capsule containing the antennas that is meant to be ingested by a cow or other ruminant animal. The bolus (100) is configured to transmit radio waves (104) in essentially an omnidirectional pattern more efficiently when the boluses (100) inside of a cow stomach than when the boluses (100) outside of the cow.
