A reflectarray antenna comprising: a deployable structure for use in establishing the reflectarray antenna, the deployable structure comprising: a base; a feed antenna for use in the reflectarray antenna; a flexible electrical element for use in the reflectarray antenna; wherein the flexible electrical element is folded in an undeployed state; wherein the flexible electrical element is unfolded in a deployed state relative to the undeployed state; and a deployment mechanism for transitioning the flexible electrical element from the undeployed state towards the deployed state; wherein the deployment mechanism includes an endless structure forming a closed loop, defining a perimeter that has a first length in the undeployed state and a second length that is greater than the first length when the endless structure transitions from the undeployed state towards the deployed state; and operatively engaged to the flexible electrical element; and an energy providing device for use in transitioning the endless structure from the undeployed state towards the deployed state; wherein, when the endless structure transitions from the undeployed state towards the deployed state, the flexible electrical element is configured to transition from being folded in the undeployed state towards being unfolded; wherein the endless structure is an endless pantograph structure; the deployment mechanism comprises a plurality of tapes (132A-132D) with each tape having a first end that is operatively connected to the base and a second end that is operatively connected to the endless pantograph structure; wherein each tape of the plurality of tapes (132A-132D) is adapted to transition from an undeployed state in which the endless pantograph structure is located at a first position relative to the base towards a deployed state in which the endless pantograph structure is located at a second position relative to the base that is a greater distance from the base than the first position; and wherein the flexible electrical element comprises a two-layer reflectarray membrane supporting an array of radiating elements. a base; a feed antenna for use in the reflectarray antenna; a flexible electrical element for use in the reflectarray antenna; wherein the flexible electrical element is folded in an undeployed state; wherein the flexible electrical element is unfolded in a deployed state relative to the undeployed state; and a deployment mechanism for transitioning the flexible electrical element from the undeployed state towards the deployed state; wherein the deployment mechanism includes an endless structure forming a closed loop, defining a perimeter that has a first length in the undeployed state and a second length that is greater than the first length when the endless structure transitions from the undeployed state towards the deployed state; and operatively engaged to the flexible electrical element; and an energy providing device for use in transitioning the endless structure from the undeployed state towards the deployed state; wherein, when the endless structure transitions from the undeployed state towards the deployed state, the flexible electrical element is configured to transition from being folded in the undeployed state towards being unfolded; wherein the endless structure is an endless pantograph structure; an endless structure forming a closed loop, defining a perimeter that has a first length in the undeployed state and a second length that is greater than the first length when the endless structure transitions from the undeployed state towards the deployed state; and operatively engaged to the flexible electrical element; and an energy providing device for use in transitioning the endless structure from the undeployed state towards the deployed state; wherein, when the endless structure transitions from the undeployed state towards the deployed state, the flexible electrical element is configured to transition from being folded in the undeployed state towards being unfolded; wherein the endless structure is an endless pantograph structure; the deployment mechanism comprises a plurality of tapes (132A-132D) with each tape having a first end that is operatively connected to the base and a second end that is operatively connected to the endless pantograph structure; wherein each tape of the plurality of tapes (132A-132D) is adapted to transition from an undeployed state in which the endless pantograph structure is located at a first position relative to the base towards a deployed state in which the endless pantograph structure is located at a second position relative to the base that is a greater distance from the base than the first position; and wherein the flexible electrical element comprises a two-layer reflectarray membrane supporting an array of radiating elements.