Abstract: A method and apparatus for classifying signals into a multiplicity of signal classes which employs discriminant functions of low-complexity discriminant variables that are computed directly from the passband signal. The method can be applied to the problem of classifying voiceband data (VBD), facsimile (FAX), native binary data, and speech on a 64 Kbps digital channel. In a hybrid two stage classification system, the first stage employs linear discriminant functions to make classification decisions into a smaller number of possible preliminary signal classes. The decisions of the first stage are then refined by a second stage that uses nonlinear discriminant functions such as quadratic or pseudo-quadratic functions. The second stage of a hybrid classifier then assigns the signal into a larger number of possible classes than does the first stage of the classifier alone.

Abstract: Whether in a SONET or a dense-WDM (DWDM) transport environment, we can expect to see a continuance of the two main survivable architectures: ring and mesh. The differing advantages of these technologies has allowed both of them to find applications, although they are usually deployed and operate quite separately. To date, the problem of optimally combining ring and mesh technologies into a single integrated transport design remains largely unstudied. This patent document presents a planning principle and related optimization theory to strategically embed rings into a mesh network, with the purpose of obtaining a lower total design cost than that of either a pure-mesh or pure-ring design. The new design approach is based on a recently developed insight into the nature of spare capacity requirements in a mesh-restorable network. So-called “forcer” analysis identifies the spans that drive the dimensioning of spare quantities in the network.

Abstract: An electro-optic modulator structure for particular use in narrowband optical subcarrier systems. A traveling wave is established across the active region of the device, instead of a standing wave. This is accomplished through the use of a directional resonator structure that prevents reverse-traveling waves from being established within the resonator. Hence, the electric field is applied to the traveling optical wave in a similar fashion to a traveling-wave modulator, except that the traveling wave has a much greater amplitude due to the build-up of energy inside the resonator. Since the modulator is operated in a traveling-wave fashion, it can be tuned to operate at any frequency using tuning elements, regardless of the length of the active region. Furthermore, the microwave and optical signals can be velocity-matched to mitigate optical transit time effects that are normally associated with a resonant modulator utilizing a standing-wave electrode structure.

Abstract: This invention modulates voice signals so that the radio waves behave the same in the radio medium as sound waves would in the acoustic medium. This is accomplished by segmenting the voice signal and compressing the segments in time before transmitting them through the radio channel. If the compression factor is correct, the distortion sounds natural to the ear because the characteristics of the radio channel match those normally encountered in the acoustic channel. The radio signal will then inherit many of the good properties of acoustic voice signals including resistance to flat fading and tolerance of frequency selective fading.

Abstract: A phase modulator for direct wideband linear phase modulation of a microwave continuous wave carrier signal which is suitable for many analog and digital phase or frequency modulation techniques. Linear phase modulation range in excess of 360 degrees is provided as a result of linear variation in the modulating signal. A conditioned baseband modulating signal is injected into a highly linear fractional range phase shifter, operating at a subharmonic of the desired output frequency. A nonlinear circuit is used to perform frequency and instantaneous phase multiplication, thus expanding the linear phase modulation range to greater than 360 degrees at the desired output frequency. With special conditioning of the baseband modulating signal, the phase modulator can be made frequency agile in ultra-small frequency steps, without requiring a stable, frequency agile reference signal or frequency synthesizer.

Abstract: An apparatus for modulating information bearing symbols onto an optical carrier includes a polybinary coder that operates on a binary information signal to produce an envelope compatible polybinary signal; and an optical single sideband modulator that modulates an optical carrier with the envelope compatible polybinary signal to produce a single sideband optical signal. This provides an improvement over both polybinary signaling and optical single sideband. This action combines the chromatic dispersion advantages of SSB modulation with the DC level and bandwidth reduction of duo-binary coding.

Abstract: An architecture for capture and generation, and a set of methods for characterization, prediction, and classification of traffic in packet networks are disclosed. The architecture consists of a device that stores packet timing information and processes the data so that characterization, prediction, and classification algorithms can perform operations in real-time. A methodology is disclosed for real-time traffic analysis, characterization, prediction, and classification in packet networks. The methodology is based on the simultaneous aggregation of packet arrival times at different times scales. The traffic is represented at the synchronous carrier level by the arrival or non-arrival of a packet. The invention does not require knowledge about the information source, nor needs to decode the information contents of the packets. Only the arrival timing information is required. The invention provides a characterization of the traffic on packet networks suitable for a real-time implementation.

Abstract: The invention is a radio terminal that co-ordinates with similar terminals around it to form a time division multiple access (TDMA) network. No base station or special devices are needed to manage the network. The terminals autonomously establish the critical functions that form the backbone of the network including routing and synchronization. Once established, any terminal can send radio messages through the network using any modulation format, analogue or digital, that meets the network's bandwidth, timing, and power specification. Terminals are able to reach destinations beyond their range by routing signals through neighboring terminals. The routing algorithm is simplified considerably by exploiting the broadcast nature of radio waves and allowing the signal to take more than one path through the network at the same time.

Abstract: A method and apparatus for harmonically upconverting a phase and/or amplitude modulated subcarrier signal to a higher frequency through a non-linear optical link is disclosed. The method requires that a bandpass signal, with a carrier frequency at a submultiple of the desired radio transmission frequency, be frequency translated in a non-linear two-port device. To avoid the inherent distortion inflicted on the information signal in harmonic upconversion, a predistortion technique is outlined. This consists of phase compression in the case of a phase modulated signal, amplitude scaling in the case of amplitude only and combined phase-amplitude predistortion for QAM type signals. With predistortion on the subcarrier signal input to the non-linear two-port, the resulting upconverted signal may be transmitted in a standard form suitable for demodulation at the signal destination without special equipment.

Abstract: Channel coding is used on the forward link of a CDMA cellular telephone network to allow the CDMA mobile channel decoder to perform error correction. On a wireless link, channel code performance is improved by providing the channel decoder with an estimate of the reliability of each received symbol. This reliability information is typically the ratio of desired signal energy to interference plus noise variance at the channel decoder input. This invention improves CDMA mobile channel decoder performance using a new technique for calculating more accurate estimates of the signal to interference plus noise ratio at the input of the mobile channel decoder.

Abstract: A method for restoring traffic in a network. The network includes plural distinct nodes interconnected by plural distinct spans, each span having working links and spare links. Each node has a digital cross-connect switch for making and breaking connections between adjacent spans forming span pairs at a node. Cross-connections between spare links in adjacent spans are made such that sets of successive nodes through which the adjacent spans form span paths form closed paths. A method of finding and construction closed paths is described in which statelets are broadcast through the network. In a preferred method of implementation of the method, the statelet broadcast occurs not in response to a network failure, but across the entire network before any particular span failure and may be carried out during normal network operations as a continual re-configuration of the network.

Abstract: In a wireless terminal used in a telecommunications system in which control bits are sent from a base station to a wireless terminal (mobile station) to control the transmitted power of the wireless terminal, a (linear) predictor is used at the wireless terminal to predict the accumulation of the received power control bits received by the mobile station, and use the difference of two successive predictor outputs to adjust the output power of the mobile in a multi-level (or continuous) increments fashion.

Abstract: A parallel-summation logarithmic amplifier is described that uses a novel topology of cascaded and parallel amplifiers to achieve extremely high bandwidth. Included in the topology is a unique delay matching scheme for logarithmic amplifiers that is amenable to fabrication in integrated circuit form. The result is flat group delay over broad frequency ranges and different power levels. The resulting log amplifier is suitable for radar applications and for use in high data rate fiber-optic networks. Also described is a unique design process that yields a set of amplifier gains that closely approximate a logarithm. Also described is the novel idea of using a parallel feedback amplifier (PFA) in piecewise-approximate logarithmic amplifiers. This innovation allows for the design of broadband amplifiers with significantly different gains and similar phase characteristics, which is extremely useful when designing high-frequency logarithmic amplifiers.

Abstract: Ongoing growth in transport demand is served while deferring or eliminating expenditure for additional capacity by reclaiming the protection capacity and inefficiently used working capacity in existing multi-ring network. Reclamation is through re-design of the routing and restoration in the network using mesh principles within the pre-existing ring capacities. The installed working and protection capacity of existing rings is viewed as a sunk investment, an existing resource, to be “mined” and incorporated into a mesh- operated network that serves both existing and ongoing growth. Three ways of approaching the idea are given. The last is a detailed planning model for minimum cost evolution out to a given total growth multiplier (or a scenario of individual future growth multipliers on each O-D pair) that considers the costs of new mesh capacity additions, nodal costs for mesh access to existing ring working and protection capacity and selective ADM conversions and re-use decisions.

Abstract: A method of designing a telecommunications network, the method comprising the steps of A) for all working demand flows required to be routed in the telecommunications network, finding an initial topology of spans between nodes in the telecommunications network that is sufficient for routing all working demand flows, while attempting to minimize the cost of providing the spans; B) given the initial topology of spans identified in step A, finding a set of additional spans that ensures restorability of working demand flows that are required to be restored in case of failure of any span in the initial topology of spans, while attempting to minimize the cost of providing additional spans; and C) starting with the initial topology of spans and the additional spans identified in step B, finding a final topology of spans between nodes in the telecommunications network that attempts to minimize the total cost of the final topology of spans, while routing all working demand flows and ensuring restorability of working d

Abstract: A new DTX-MAC protocol is proposed for a cellular radio telecommunications system with many users. Several users are allowed to transmit packets within a time-slotted frame structure. Direct sequence spread spectrum technique is used to spread the packets, and all packets within the frame are spread using the same spreading sequence. The packets overlap, but each packet begins within a distinct slot of the frame. Each slot, or mini-slot, since it is much shorter than the packet, is dedicated to one of the mobile terminal users. Collisions between packets are prevented by appropriate selection of the duration of the mini-slot. Packets may be ARMs, user data, or both.

Abstract: A broadband compact antenna comprises an electric dipole or monopole coupled or connected in parallel to a slot antenna. The slot antenna is composed of a flat, square or rectangular conducting sheet with a slot having a variety of possible shapes including a bow-tie or rectangle. The slot is then fed at the center by a coaxial transmission line with its outer conductor bonded to the sheet. To obtain broadband characteristics and compactness, a dipole or monopole, formed using either wire, flat strips or shapes formed in sheets of metal, is located in close proximity to the center of the slot.

Abstract: A Method for restoring traffic in a network. The network includes plural distinct nodes interconnected by plural distinct spans, each span having working links and spare links. Each node has a digital cross-connect switch for making and breaking connections between adjacent spans forming span pairs at a node. Cross-connections between spare links in adjacent spans are made such that sets of successive nodes through which the adjacent spans form span paths form closed paths. A method of finding and construction closed paths is described in which statelets are broadcast through the network. In a preferred method of implementation of the method, the statelet broadcast occurs not in response to a network failure, but across the entire network before any particular span failure and may be carried out during normal network operations as a continual re-configuration of the network.

Abstract: A complex baseband model of the power amplifier within a DSP domain is used to develop a feedback signal that would be equivalent to the optimum negative feedback used for the analog amplifier. Once the feedback signal is available, it can be processed to compensate for the effects of the group delay and for optimum loop gain, hence resulting in a broadband response with no theoretical limitations on the linearization of the amplifier.

Abstract: A method to increase the capacity efficiency of span-restorable mesh networking on sparse facility graphs. The new approach views the network as a “meta-mesh of chain sub-networks”. This makes the prospect of WDM mesh networking more economically viable than with previous mesh-based design where the average nodal degree is low. The meta-mesh graph is a homeomorphism of the complete network in which edges are either direct spans or chains of degree-2 nodes. The main advantage is that loop-back type spare capacity is provided only for the working demands that originate or terminate in a chain, not for the entire flow that crosses chains. The latter “express” flows are entirely mesh-protected within the meta-mesh graph which is of higher average degree and hence efficiency for mesh restoration, than the network as a whole. Nodal equipment savings also arise from the grooming of express lightpaths onto the logical chain-bypass span.