摘要:
A method for synchronizing a CDMA receiver to a transmitter when an adaptive antenna is utilized to receive transmitted data, wherein a receiving antenna system is adapted between a 360° reception angle pattern (i.e., an omni-directional pattern) and a fixed reception angle (i.e., a directional pattern) by permitting the receiver to identify a pilot signal having the largest magnitude. The receiver minimizes interference from other pilot signals by steering antenna pattern nulls toward other transmitters. As a result, the time required for the receiver to acquire a valid pilot signal is significantly reduced.
摘要:
A method and repeater are described for repeating using a time division duplex (TDD) radio protocol. A signal is transmitted from a first station to a second station using a downlink and an uplink. The signal can be detected on the uplink or the downlink. The repeater can synchronize to time intervals associated with the detected signal that are measured during an observation period. The signal can be retransmitted from the second station to the first station if the signal is detected on the uplink and re-transmitted from the first station to the second station if the signal is detected on the downlink. A gain value associated with the downlink can be used to establish a gain value associated with the uplink.
摘要:
An antenna configuration includes two closely spaced antennas each positioned so as to be orthogonally polarized with respect to the other. The antenna configuration increases antenna isolation and reduces electromagnetic coupling between donor side antenna and repeat side antenna. The antennas include printed dipoles connected to respective transceivers through respective baluns to balance the non-symmetrical portions of the antenna feed paths to reduce unwanted radiation therein. Printed features such as chokes and non-symmetrical and non-parallel structures are preferably included in the ground plane of a multi-layer circuit board to reduce or eliminate circulating ground currents.
摘要:
A wireless network includes at least one Multiple Input Multiple Output (MIMO) wireless network station and two or more physical layer repeaters. Each of the physical layer repeaters is for receiving a wireless signal to or from the at least one MIMO wireless network station and re-transmitting the wireless signal while continuing to receive the wireless signal. The repeaters may be either frequency translating repeaters or non-frequency translating repeaters.
摘要:
An antenna apparatus, which can increase capacity in a cellular communication system or Wireless Local Area Network (WLAN), such as an 802.11 network, operates in conjunction with a mobile subscriber unit or client station. At least one antenna element is active and located within multiple passive antenna elements. The passive antenna elements are coupled to selectable impedance components for phase control of re-radiated RF signals. Various techniques for determining the phase of each antenna element are supported to enable the antenna apparatus to direct an antenna beam pattern toward a base station or access point with maximum gain, and, consequently, maximum signal-to-noise ratio. By directionally receiving and transmitting signals, multipath fading is greatly reduced as well as intercell interference.
摘要:
In an illustrative embodiment of the present invention, a channel is allocated to carry messages from each of multiple subscriber units to a base station. Selected messages generated by a subscriber unit that would otherwise be transmitted over an assigned reverse link traffic channel are instead encoded and transmitted to the base station over a shared reverse link channel. Preferably, the shared reverse link channel is time-slotted and each subscriber unit transmits information to the base station in an assigned time slot so that the base station receiving the messages can identify from which subscriber unit a message is sent. Certain bits in a time slot of the shared channel as set by a subscriber unit can be used to communicate a particular message to the base station. For instance, a single bit that is transmitted in a time slot can be encoded to transmit a substitute message from one of the multiple subscriber units to a base station, where the setting of the bit itself indicates a message type.
摘要:
A frequency translating repeater (120) for use in a time division duplex (TDD) radio protocol communications system includes local oscillator (LO) circuits (210, 310, and 410) to facilitate repeating by providing isolation, reduced phase noise, reduced pulling, and the like. Tunable LOs (441, 442) can be directly coupled to down-converters (413, 414) and up-converters (426, 427) for increased isolation, reduced phase noise, less stringent frequency accuracy, and a reduced potential for pulling.
摘要:
An illustrative embodiment of the present invention supports the transmission of data to a user on an as-needed basis over multiple allocated data channels. Data packets are transmitted in time-slots of the allocated data channels to corresponding target receivers without the need for explicitly assigning particular time-slots to a target user well in advance of transmitting any data packets in the time-slots. Instead, each data packet transmitted in a time-slot includes a header label or preamble indicating to which of multiple possible receivers a data packet is directed. The preamble also preferably includes decoding information indicating how a corresponding data payload of the data packet is to be processed for recapturing transmitted raw data.
摘要:
In a wireless telecommunications network, wireless transmissions are carried via an RF medium between users and a central wireless transceiver, or base station processor. A subscriber access unit connected to a user device such as a user PC is employed to transmit wireless messages to and from the base station processor. Multiple, simultaneous wireless transmissions to the base station from different subscriber access units can have a tendency to interfere with each other. Subscriber access units employing an omnidirectional antenna r which are highly mobile will tend to experience more interference than stationary users or subscriber access units employing a directional antenna. The allocation of wireless transmission resources to retransmit wireless messages over a lossy link can have a detrimental effect on wireless resources available for other users. A system which allows a subscriber access unit to register device capabilities with a base station processor to determine the degree to which a particular subscriber access unit may be prone to interference provides computation and adjustment of transmission constraints for each subscriber access unit accordingly to maximize throughput.
摘要:
A non-frequency translating repeater (110, 210, 300) for use in a time division duplex (TDD) radio protocol communications system includes detection retransmission and automatic gain control. Detection is performed by detectors (309, 310) and a processor (313). Detection can be overridden by processor (313) using logic elements (314). Antennae (220, 230) having various form factors can be used to couple a base station (222) to a subscriber terminal (232) which can be located in a sub-optimal location such as deep inside a building or the like.