An asymmetric bandwidth communication system enables wireless communication between interrogators/readers and transponders/tags. A transponder transmits TDCIR (Time Domain Carrierless Impulse Radio) signals in the uplink direction and receives non-TDCIR signals, such as electromagnetic continuous waves, in the downlink direction. The transponder may receive partial or whole power from non-TDCIR signals. The TDCIR utilizes electromagnetic impulses with short duration and ultra wide bandwidth. It offers high data rate reliable communication at low power and design complexity. It also demonstrates resilience against path fading, selective absorption and reflection by physical matters and excellent location determination capabilities.