Repeater system for strong signal environments
View Patent ↗A repeater system combines co-located antennas, an intentional imbalance in signal amplification between downlink and uplink, stability management and an amplification indicator to create a user-installed solution to co-channel interference within cellular systems, in strong signal environments such as elevated locations or high-rise building. The invention may be particularly relevant to cellular systems, such as CDMA, that allow limited imbalance between uplink and downlink path losses, thus enabling the design of an inexpensive repeater with a weaker or non-existent uplink, and which creates moderate signal amplification for selected line-of-sight signals, defeating co-channel interference over a small area. The difference in signal amplification on the downlink and uplink is maintained at a level below the capacity of the system to support imbalance, guaranteeing reliable cellular calls.
1. The repeater system in a mobile communication system comprising a plurality of base stations and subscriber units that communicate via RF signals, comprising:
a plurality of repeaters, each of the plurality of repeaters comprising
a base-side antenna to receive at least one selected downlink signal and to generate a received downlink signal;
an amplifier receptive of the received downlink signal, to amplify a level of the received downlink signal and to generate an amplified downlink signal; and
a subscriber-side antenna, located proximate to the base-side antenna and receptive of the amplified downlink signal, to transmit RF signals representative of the amplified downlink signal within a local area to at least one of nearby subscriber units or repeaters,
wherein a first repeater of the plurality of repeaters is configured to receive at least one selected downlink signal from at least one of the plurality of base stations, and
wherein a second repeater of the plurality of repeaters is configured to receive transmitted RF signals from the first repeater, said second repeater further comprising uplink amplification which is substantially less than downlink amplification, and
wherein said second repeater is further configured, in an uplink direction, for the subscriber-side antenna to receive RF signals from the nearby subscriber units and to generate a received uplink signal, for the amplifier to receive the received uplink signal, to amplify the received uplink signal by a substantially smaller level then used in a downlink direction and to generate an amplified uplink signal, and for the base-side antenna to receive of the amplified uplink signal and to transmit RF signals representative of the amplified uplink signal to one of the plurality of base stations.
2. The repeater system of claim 1 , wherein the second repeater operates in the uplink direction between the subscriber units and the first repeater and the presence of the second repeater in the downlink and uplink directions causes an intentional imbalance in total losses between the downlink and the uplink, in order to provide for signal enhancement in both uplink and downlink over an equivalent coverage area.