Abstract:
A method for registering a mobile station (307) in a radiotelephone communication system (300). The mobile station (307) receives system information from a base station (321), including a cell grouping level. The mobile station (307) determines if it is registered with the base station (321). If not, the mobile station (307) registers. The network controller of the radiotelephone communication system (300) automatically registers the mobile stations with all base stations defined by the cell grouping level. The mobile station (307), using the same algorithm, maintains a record of the base stations with which it is automatically registered.
Abstract:
A resynchronization method for use in a communication system, such as a second generation cordless telephone system 800, begins by determining that synchronization has been lost by a receiving unit (830). The receiving unit than mutes any transmit data and generates zero data which is combined with a pattern generated by pattern generator (812). The transmission is then received by handset (830), which detects the pattern generated by pattern generator (812) using pattern detector (850). Pattern detector (850) then generates a pattern detected signal (852) which causes handset (840) to also stop sending data and generate a pattern accompanied by zero data. Base station (830) detects the pattern and again generates another pattern accompanied with zero data which is transmitted to handset (840). Handset (840) after decoding the pattern for the second time begins to resumes the normal transmission of data to base station (830).
Abstract:
A method for re-establishing a communication link that has been lost between a portable unit (406) and a fixed unit or base station (402) provides for a way of quickly re-establishing the lost communication link, on the previously used RF channel. The method is begun by transmitting a link re-establishment code word (900) using MUX 1 after determining that synchronization has been lost (502) for a predetermined period of time (504). This is followed by automatically switching the portable unit (406) from MUX 1 to MUX 3 communication protocol. Followed by re-establishing communication (re-establish synchronization) between the portable (406) and base station (402) in MUX 3 and switching the two communication devices (402 and 406) back to MUX 1 after the communication link has been re-established. The same steps can be followed by base site (402) if it had been the first to detect loss of the communication link.
Abstract:
A method and apparatus for choosing the most optimum communication channel in a system (100) having a plurality of communication channels provides for reduced interference and increased system capacity. By establishing a set of threshold levels and comparing these threshold levels to receive signal strength level measurements for each of the communication channels, a communication device originating a call can be guaranteed of establishing communication using the communication channel with the least chance of being affected by interference or of affecting other channels already in use.
Abstract:
A low profile antenna includes a rectangular driven element and a rectangular ground plate spaced from the driven element. A coaxial transmission has its center conductor connected to an end of the driven element and its ground connection connected to the end of the driven element spaced from the center conductor connection. An inductance is coupled between the coaxial cable shield and the ground plate.
Abstract:
A low-profile antenna for operating in the 800 to 900 mHz range and especially suited for use with portable, hand-held electronic apparatus. The antenna features printed circuit board construction for precision fabrication, broadband operations and enhanced efficiency. The antenna includes a driven element in close association with a parasitic element printed on one surface of the printed circuit board in a side-by-side, parallel relation. A conductive strip is included on the other side of the board spanning the free ends of the driven and parasitic elements to enhance the coupling therebetween.
Abstract:
A low profile antenna comprised of a driven element and a parasitic element spaced above a ground plane. The driven element is connected at one end to the feedpoint of the radio device to which it is attached, the opposite end thereof being free. The parasitic element is connected to the ground plane by its end nearest the feedpoint, the opposite end thereof being free. In the preferred embodiment the parasitic element length and the driven element length are both approximately equal to a quarter wavelength at the operating frequency.