RADIO COMMUNICATION TRANSMITTERS RECEIVERS

Brand	Owner (click to sort)	Address	Description
CMC	CANADIAN MARCONI COMPANY	600 DR. FREDERIK PHILIPS BOULEVARD SAINT-LAURENT, QUEBEC H4M 2S9 Canada	Radio Communication Transmitters and Receivers; Electronic Direction Finding and Distance Measuring Transmitters and Receivers Using Electromagnetic and Sound Waves; Piezoelectric Transponders; Aircraft and Aircraft Engine Monitoring Transducers, Analysers and Displays; Data Switching Exchange Units; Inductors and Transformers; Illuminated Instrumentation Panels; Power Supplies; Radar Transmitters and Receivers; Radio Telephone Transmitters and Receivers; Hybrid Micro Circuits; Printed Circuit Boards; and, Alpha-Numeric Display Units;
W	WILCOX ELECTRIC COMPANY, INC.	KANSAS CITY, MO.	RADIO COMMUNICATION TRANSMITTERS AND RECEIVERS;
	Where the owner name is not linked, that owner no longer owns the brand

Technical Examples

Transmitting non-polluting dummy pilot signals in a wireless communication network permits estimation of the downlink propagation channels between a number of joint transmitters and a lesser number of receivers. With fewer receivers than transmitters, loop back information from the receivers is not sufficient to determine the downlink propagation channels between the transmitters and receivers. For N transmitters and M receivers, (N-M) dummy pilot symbols are transmitted to facilitate downlink channel estimation. Each dummy pilot signal is transmitted to an imagined or dummy receiver that is virtually located such that its downlink channel coefficient vector is orthogonal to those of the real receivers. Transmit pre-filtering based on estimated propagation channels is applied to the information signals for the real receivers and to the dummy pilot signals. The extent to which the dummy pilot signals interfere at each receiver is an indication of mismatch between estimated and actual propagation channels.