Abstract:
A mobile subscriber unit (MS) location method and system in a spread spectrum channel coding system uses a known spread spectrum location beacon channel (34) that is time division multiplexed with normal code division multiplexed channels (36). Each base station (12, 14 and 16) in a defined service area transmits the known time division multiplexed spread spectrum location beacon signal (34), such as a known location channel, as a spread spectrum location beacon signal at a same time interval. Mobile subscriber units (18) receive the spread spectrum location beacon signal (34) time division multiplexed with the normal CDMA channels (36) and determine their own location using location techniques such as trilateration. Preferably, all of a base station's transmit power is assigned to this special known location channel (34) during transmission.
Abstract:
In a TDMA cellular network, there is provided a mechanism for shared-carrier frequency-hopping. It comprises: allocating on a frame basis within a reuse diameter to one coverage area (A-I) during certain timeslot(s) at least one from a pool of TDM frame-hopped carriers and allocating on a frame basis within that carrier reuse diameter to another coverage area (A-I) during certain other, substantially non-overlapping timeslot(s) that frame-hopped carrier, all in substantially non-interfering time-synchronism with any proximal reuse of that carrier, whereby the advantages of frequency hopping are obtained. Stated differently, it comprises: at one instant in time, allocating within a reuse diameter to one coverage area (A-I) at least one of a plurality of hopped carriers and at that same instant in time, allocating within that carrier reuse diameter to another coverage area (A-I) another of that plurality of hopped carriers, all in time-synchronism with any proximal reuse of that carrier. The control and access carriers may also be included in the hopping pool, causing certain timeslots to be hopped on a sequence different from the others. The pool of hopped carriers is further apportioned among co-located sites into hopping groups, thereby reducing intra-system synchronization requirements. To solve the near/far problem, TDM timeslots bordering hopping boundaries are preferentially allocated to less distant mobile users.
Abstract:
A communication system time division multiplexes the use of spreading codes. The communication system accepts information (301, 302) from at least two users and codes each users information utilizing error correction coders (303, 306). The coded information is then time multiplexed by a multiplexer (312) into timeslots. The output of the multiplexer (312) is spread by a common spreading (Walsh) code, scrambled with a pseudo-noise sequence, and conveyed to a modulator for transmission. In this manner, information for two users may be transmitted utilizing only a single spreading (Walsh) code.
Abstract:
On décrit un procédé et un appareil servant à échanger des signaux communiqués entre une installation de base éloignée (60, 61, 62, 63, 64 ou 65) et une installation centrale (205) d'un système cellulaire, sur une ressource de communication qui est également utilisée à l'occasion pour échanger des signaux entre l'installation de base éloignée et des postes de communication mobiles.
Abstract:
A WLAN access point (111) is synchronized with a Wide Area Network (WAN) (105) via either a backhaul connection (115), or via hardware of the WLAN access point (111) suitable for receiving and decoding a synchronization timing signal from the WAN (105). The WLAN access point (111) may then transmit a beacon signal during a defined time window. The mobile station (101) is aware of the time window and only powers its WLAN transceiver equipment on during the appropriate window. Because the WLAN access point (111) is synchronized to the WAN (105), the mobile station (101) is able to anticipate the appropriate time window for power up. When the mobile station detects the WLAN access point (111) beacon, it notifies the WAN (105), via a WAN base transceiver station (BTS) (107) and proceeds to hand over idle mode signaling from the serving BTS (107) to the WLAN access point (111).
Abstract:
A system including a backup server (111) and corresponding methods (FIG. 4, FIG. 5), for backing up a memory (207) of a wireless subscriber device (101). The method involves creating an archived representation of the memory image (405, 505) in a backup server and scanning modified representations of the memory image (407, 507) for abnormalities, such as viruses or other malicious files. If a problem has occurred, the memory of the wireless subscriber device can be restored (409, 509) using an archived representation of the memory image.
Abstract:
A subscriber device (2) includes a long code generator (12) and a modifier (30) for generating a spread bit stream with a predetermined error pattern that is transmitted by a transmitter (16) at the subscriber device (2) to a base station (3). The base station (3) identifies the current subscriber device properties by identifying the error pattern and subsequently compares the current subscriber device properties with a knowledge base of subscriber device software properties associated with the error pattern in the spread bit stream. The knowledge base is stored in a memory source (4).
Abstract:
A group of wireless apparatus (106A-106N) in a wireless local area network (LAN), each receives information from a wireless wide area network (WAN). The plurality of proximal apparatus (106B-106N) within the group of wireless apparatus (106A-106N), each receives the same information destined for a destination apparatus (106A) from WAN, then retransmits the same information to the destination apparatus (106A), using the short range LAN, which combines the information to improve reliability.
Abstract:
To mitigate the adverse effects of the load imbalance phenomenon prevalent in spread spectrum, multi-carrier wireless communication systems, the system beneficially employs the use of handoff as a means for balancing the call traffic (commonly referred to as "load") among a plurality of carriers within the communication system. The multi-carrier wireless communication system monitors (214) a plurality of metrics corresponding to the loading of each of the plurality of carriers in the communication system and, based upon the metrics, will handoff (220) call traffic to and between the plurality of carriers, thereby mitigating the adverse effects associated with the load imbalance, in accordance with the invention.
Abstract:
A method of maintaining call quality in a communication system by communicating between a base site (101) and a communication unit (113) on a first channel. The communication unit (113) monitors the downlink communication signal (116) transmitted by the base site (101) and determines a characteristic of the first channel. The communication unit (113) is then handed off to a second channel having a less aggressive reuse pattern, based on the characteristic of the first channel.