BACKGROUND

Recent technological improvements have dramatically improved the ability to communicate across vast distances. Extensive fiber optic and satellite networks now allow remote parts of the world to communicate with one another. However, by spanning across these great distances, such as across the Atlantic or Pacific Oceans, fiber optic cables can incur a round-trip latency or time lag of about 60 msec or more. Satellite communications can experience even greater lag times. In many cases, this high latency cannot be overcome because it is inherent in the communications medium and equipment. For example, light may traverse an optical fiber 30-40% more slowly than a radio wave traveling the same distance through free space. Fiber optic networks typically require multiple repeaters that further increase latency. While generally not problematic in a number of circumstances, this high latency can cause unacceptable delays in the execution of time sensitive activities, especially time sensitive activities that require complex logic and/or are dependent on conditions that rapidly change. These latency issues can for example create problems for a whole host of activities, such as in the operation and/or synchronization of distributed computer systems, scientific experiments with geographically large sensor arrays, and telemedicine/diagnostic activities, to name just a few. In one particular example, orders to buy and sell securities or other financial instruments in world markets typically rely on communications links that carry data and instructions over systems using fiber optic lines, coaxial cables, or microwave communication links. Any delays in executing an order, such as caused by the high latency across fiber optic lines, can lead to significant financial losses.

In order to send information across broad distances by radio communication, a radio signal may take advantage of skywave propagation where the signal “bounces” between the earth and the upper atmosphere to traverse long distances across the globe. This can advantageously result in communications traveling rapidly beyond line of sight. However, it can also mean that transmitted signals may never reach the intended receiving station because the signals may never return to earth at that specific location. Predicting the likelihood of a transmitted signal reaching a particular location on earth via skywave propagation can be a challenge given that skywave propagation is affected by multiple unrelated variables such as weather conditions, sunspot cycles, changes in solar radiation, the time of day, the desired transmission frequency, the type of antenna, the height of the antenna above the ground, and the topography of the ground around the transmission site.

SUMMARY

A unique communication system and method has been developed to address the above-mentioned latency issues as well as other issues. In the communication system, command data is transmitted so as to be received at a receiving station before (or at the same time) triggering data is received. The command data includes one or more directives, instructions, algorithms, and/or rules for controlling a machine, such as a computer and/or mechanical device, to take one or more actions. For example, the command data in one form includes a program for buying and/or selling particular options or stocks at certain price levels, ranges, and/or based on other conditions. Command data is typically (but not in all circumstances) larger in size than the triggering data such that the command data takes longer than the triggering data to transmit over communication links having the same data bandwidth. The triggering data includes information identifying one or more commands in the command data to execute. For example, the triggering data can identify one or more particular options in the command data that identifies the particular stock (or multiple stocks) to purchase at a particular price (or prices).

In one example, the command data is transmitted over a communication link that has high bandwidth and high latency, such as over a fiber optic cable, and the triggering data is transmitted over a communication link that has low bandwidth and low latency, such as through sky-wave propagation by refracting and/or scattering radio waves from the ionosphere. The relatively small-sized triggering data is then able to be more quickly received at a receiving station than if the triggering data was transmitted over the high bandwidth and high latency communication link provided by fiber optic cable. This communication system and method dramatically reduces the time to execute complex time-sensitive actions, such as financial transactions, over large distances at remote locations. In one form, this technique is used to remotely perform actions past the radio horizon, such as for transatlantic communications. This technique can be adapted for one-way type communications or even two-way type communications.

This unique communication system and method in one example uses multiple communications links. In one form, the communication links use different communications media. Such a system might be used, for example, to transmit a large collection of preprogrammed commands or rules over a high latency/high bandwidth link in advance of a triggering event which may be a market event, news report, a predetermined date and time, and the like. This set of rules or preprogrammed actions may be sent as a software update to an executable program, or as a firmware upgrade for a Field Programmable Gate Array (FPGA). When a triggering event occurs, triggering data can be sent over a low latency/low bandwidth link alone, or over both links, causing the preprogrammed commands to be executed as planned.

In one example of the system, the low latency/low bandwidth communications link uses radio waves to transmit data in concert with the higher latency/high bandwidth communications link which may be a packet switched network operating over fiber optic cables. Such a combination may include various combinations with widely varying differentials between the high and low latency links. The low latency link may use high frequency (HF) radio waves to transmit over a propagation path between North America and Europe. Radio waves may transmit, for example, with a one-way latency of 20 to 25 ms or less (40 to 50 ms round trip). A higher latency link may carry data over a different propagation path, or perhaps through a different medium between the same two continents that, for example, may have a latency of about 30 ms or more one-way, or 60 ms or more both ways.

The latency may be reduced and the reliability of the low latency/low bandwidth link may be improved by preparing the site of the transmitting antenna to optimize the number of hops along the propagation path, and/or increase the likelihood of the signal returning to earth at a receiving station or repeater. The site of the transmitting antenna may be chosen or modified according to manage the interaction of the transmitted electromagnetic energy with the antenna and the ground for the given range of desirable transmission frequencies.

For example, modifications to the ground elevation at the antenna transmission site may include placing the antenna at the top of a natural landform such as a hill or above a valley. The ground elevation could further be modified by adding or removing soil in the area around the antenna. In this way, the interaction between the radio waves and the ground may be controlled to cause radio waves to be transmitted at a given angle relative to the earth. Choosing this angle may then reliably control the skip distance and the number of hops between the transmitting antenna in the receiving antenna for a desired range of frequencies and time of day.

Other variations of site preparation may include positioning the transmitting antenna near a body of water such as an ocean, a saltmarsh or other brackish water. In one configuration, the antenna would float on a device such as a barge, buoy or raft. In another configuration, pylons or towers would be constructed in the body of water in order to elevate the antenna above the surface of the water. In another variation, the height of the antenna is adjustable (i.e., may be raised or lowered) so as to compensate for changing conditions, or switching between different transmission frequencies.

In another aspect, overall security of the system may be enhanced by sending a continual stream of actions and/or triggering messages over the separate communications links to confuse malicious third parties and discourage attempts to intercept and decipher future transmissions. These messages may be very short, or intermingled with various other transmissions which may go on continuously, or for only short periods of time on a predetermined schedule. In a related aspect, security may be enhanced by sending short messages over skywave propagation on one or more frequencies, or by sending small parts of a message on several frequencies at the same time. Various additional techniques may also be employed to enhance security such as encryption, two-way hashing, and the like, which may incur additional latency in both links.

So as to aid in appreciating the unique features of this communication system and method, the communication system and method will be described with reference to executing trades of stocks, bonds, futures, or other financial instruments, but it should be recognized that this system and method can be used in a large number of other fields where latency is a concern, such as for distributed computing, scientific analysis, telemedicine, military operations, etc.

Further forms, objects, features, aspects, benefits, advantages, and embodiments of the present invention will become apparent from a detailed description and drawings provided herewith.

