Abstract: A system and method for transmitting a radio frequency (RF) signal in a RF bandwidth over a low bandwidth medium, e.g., in-building unshielded twisted pair (UTP) cabling, which has a transmission bandwidth below the RF bandwidth. The system has a unit for receiving the RF signal and a global reference oscillator for distributing a global reference tone of high stability to the entire system. Local oscillators controlled by this global reference tone deliver RF reference tones of high stability required for mixing the RF signal to obtain an intermediate frequency (IF) signal which is fed through the low bandwidth medium to remote sites. A 10 base T cable network, often pre-existing in many building structures, provides a suitable, cost effective low bandwidth medium for such RF communication. Two of the four twisted pair cables of a UTP cable are sufficient to support bi-directional communication.

Abstract: Individual channels are centrally and tunably selected for emission in a distributed wireless communications system. A high-frequency signal received at a central antenna is down-converted such that a selected channel corresponds to a predetermined frequency range. Non-selected channels are filtered out. The selected channel is transmitted to remote locations over commonly available transmission lines, up-converted, and re-emitted. The transmitted channel is chosen by tuning the frequency of the local oscillator used for down-conversion. A high-stability global tuning signal is used to tune and stabilize the local oscillators used for up-conversion. The global tuning signal is generated by frequency-dividing the down-conversion local oscillator signal by a fixed number, while the up-conversion local oscillator signals are generated by frequency-multiplying the global tuning signal by the same fixed number. Phase-locked loops are used for frequency multiplication and stabilization.

Abstract: A frequency band, or test band, located between the uplink and downlink frequency bands of a distributed, frequency duplexed network is used in a novel way to isolate block-level faults within the network. A test signal having frequencies within the test signal band is generated and fed into a downlink path of a branch of the communication network. When the test signal encounters a remote station having duplexing means, the test signal leaks through the duplexing means into an uplink path of the remote station. This occurs because the real filters of the duplexing means do not work perfectly, frequencies outside of the uplink and downlink bands, especially those in the test signal band, will leak through its components. The amount of attenuation of the test signal in leaking through the communication station indicates the operability status of the components therein. By monitoring the power level of the test signal in the uplink and downlink paths of the branch, faults can be quickly isolated.

Abstract: The placement of repeater or base station antennas in an in-building or urban wireless RF communications network is optimized using field measurements. Test antennas are placed at a number of sites within the coverage area, and the signal from each test antenna is measured at different locations within the coverage area. The measurement allows the simulation of the coverage provided by different arrangements of antennas. An optimum arrangement can then be chosen. The optimum arrangement of antennas is chosen by maximizing a utility function that depends on the quality of the coverage within the area and on the cost of installing an arrangement. A database of architectural categories (building plans) and measurement results for each category is built by a method of the present invention. A new building is then matched to the closest component categories in the database, thus allowing the optimization of coverage in a coverage area without the measurement of signals from nest antennas in the new building.