AN AUDIO TRANSMISSION SYSTEM FOR A COMPUTER
The present invention relates to an audio transmission system for a computer and particularly but not exclusively relates to a system for use with a portable computer.
Many computers now incorporate a sound driver or drivers, and speakers to enable the user of the computer to listen to music stored on the computer or played from an internal or external music player such as a CD or MP3 player. However such computers, and particularly smaller computers such as portable or lap top computers, typically have relatively poor quality speaker systems. It has been proposed to provide better quality add-onplug-in external speaker systems but such external speakers take up space, can add wiring, and are typically not easily
portable.
According to a first aspect of the invention there is provided an audio transmission system comprising a computer, and a PCMCIA card for the computer, the PCMCIA card comprising means to interface, in use, with the computer to receive an audio data signal from the computer and to send the data signal to a radio transmitter provided on the PCMCIA card, the radio transmitter being operative to transmit the audio signal on a carrier wave to a remote radio receiver such that the audio signal can be broadcasted from the radio receiver.
A PCMCIA card, or PC card, is a removable electronic device that adds a feature or features to a computer. PCMCIA cards can, for example, add memory, modem and networking capability, more hard drive space, or enhanced sound to a computer. Such a card is typically a plug-and- play device which typically uses a 16-bit socket on the computer, and a 68-pin connector, and is configured in accordance with standards set by the Personal Computer Memory Card International Association.
Preferably the computer is provided with a software interface that enables data to be exchanged between the PCMCIA card and the computer.
Preferably the radio transmitter is a FM transmitter operative to transmit a FM carrier wave to an FM radio receiver.
Preferably the PCMCIA card comprises an audio signal amplifier which receives and amplifies the audio signal from the computer.
Preferably the system comprises a remote control operative to control the radio receiver.
Preferably the computer comprises means operative to poll the radio receiver to determine if a command has been sent by the remote control device.
Preferably the system is provided with PCMCIA driver software operative to run on the computer, the driver software including a sound driver that allows audio data signals generated within the computer to be routed via the PCMCIA card FM transmitter.
Preferably the driver software includes means to adjust the transmitter so Ehat the frequency of the transmitted signal can be selected.
Preferably the frequency of the transmitted signal can be selected between a range of 88 MHz and 107 MHz.
Preferably the transmitter is of a limited transmitting power such that radio signals transmitted by the transmitter do not interfere with other radio broadcasts occurring on the same frequency and within a range of 10 metres of the transmitter.
Most preferably the power of the transmitter is limited such that the transmitter does not interfere with other radio broadcasts occurring on the same frequency and within a range of 5 metres of the transmitter.
According to a second aspect of the invention there is provided a PCMCIA card for a computer, the PCMCIA card comprising means to interface, in use, with the computer to receive an audio data signal from the computer and to send the audio data signal to a radio transmitter provided on the PCMCIA card, the transmitter being operative to transmit the audio data signal on a carrier wave to a remote radio receiver such that the audio data signal can be broadcasted from the radio receiver.
Other aspects of the present invention may include any combination of the features or limitations referred to herein.
The present invention may be carried into practice in various ways, but embodiments will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a schematic diagram of the audio transmission system in accordance with the present invention; and Figure 2 is a flow diagram of the system of Figure 1.
Referring to Figure 1, a PCMCIA card I for a computer 3 comprises a credit card sized outer casing containing a number of electronic components and connection means comprising a plurality of pins arranged to form, in use, an electrical connection with a corresponding socket provided on the computer 3.
The PCMCIA card 1 is provided with a software interface 5 that enables audio data to be exchanged between the PCMCIA card 1 and the computer 3.
The PCMCIA card 1 comprises an audio signal amplifier 7 which receives, in use, an audio signal from the computer 3, amplifies the audio signal, and sends the amplified audio signal to a FM radio transmitter 9 provided on the PCMCIA card. The FM transmitter 9 is controlled by software on the computer 3 and transmits the amplified audio signal on a selected frequency, via an antenna 10 on the PCMCIA card 1, to a remote radio receiver Ii remote from the computer 3. The radio receiver 11 may be a bespoke radio receiver or a standard existing radio receiver as might be found on known domestic audio systems. A remote control can be provided to control the radio receiver so as to be able to adjust the volume of the transmitted audio signal, and to select tracks or the like from the CD or MP3 player or the like used by the computer.
The PCMCIA card 1 is provided with PCMCIA driver software which is loaded onto the computer 3 (the computer 3 may auto-prompt for such software upon detecting the PCMCIA card 1). The driver software includes a sound driver that allows audio data signals generated within the computer 3 to be routed via the PCMCIA card FM transmitter 9 rather than, or in addition to, being routed through the computer's built in or plugged in speaker system.
The driver software includes means to control the transmitter 9 so that the frequency of the transmitted signal can be selected, preferably between a range of 88 MHz and 107 MHz.
Referring additionally to Figure 2, the process begins with the computer 3 determining 15 if the PCMCIA card software driver is enabled. If the driver is enabled the computer 3 then checks 17 if the PCMCIA card 1 is attached to the computer 3. If not, a warning is provided 19 to the user. If yes, the computer 3 sets 21 the FM transmitter 9 to the user selected transmitting FM frequency.
The computer 3 then enters the primary control loop 22 wherein the audio signal generated by the computer 3 is routed 23 to the transmitter 9 which transmits the audio signal to the radio receiver.
During transmission, the computer 3 also polls 25 the radio receiver 11 to determine if a command 26 has been sent by the remote control device. If a command has been sent, the computer 3 processes 27 the remote command.
During transmission the computer 3 also checks 29 if the user has requested to stop the transmission. If so, the computer 3 shuts down 31 the PCMCIA transmitter 9 and disables the audio feeds to the transmitter 9. If not, the computer 3 re-enters the main control loop 22 and begins the above process steps 23 to 29 again.
The transmitter 9 is of a limited power such that radio signals transmitted by the transmitter 9 do not interfere with other radio broadcasts occurring on the same frequency and in the same vicinity. Thus the power of the transmitter 9 is selected such that the transmitter 9 can only transmit radio signals via the PCMCIA card I to a radio receiver 11 in the building and preferably within approximately 5 metres from the transmitter 9.
The remote control device could be interfaced with existing computer audio software such as, for example, WInAMP, and other software could be provided to enable the remote control device to interface with other computer music playing software programs.